Punjab State Board Life Processes Class 10 Science Question and Answers

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Punjab State Board Class 10 Biology Chapter Life Processes Question and Answers

Question 1. What is translocation? How does it take place in plants?
Answer:

Translocation

Translocation is the transport of food and other solutes in the phloem of plants. It occurs from the region of manufacture or storage to the area of consumption in a mass flow due to the development of a turgor gradient.

Question 2. Leakage from blood vessels reduces the efficiency of the pumping system. How is leakage prevented?
Answer:

Leakage from blood vessels reduces the efficiency of the pumping system

In the area of leakage, blood platelets burst to release thromboplastin. It helps in the formation of a fibrin network in which blood cells accumulate to seal the area.

Read And Learn More 10th Class Science Solutions

Question 3. Mention the two main components of the transport system in plants. State one function of each.
Answer:

The two main components of the transport system in plants

  1. Plants have two components in their transport system, the xylem and phloem. Xylem transports sap (water and minerals) by means of its tracheary elements of vessels and tracheids.
  2. The movement is unidirectional from root to aerial parts. Phloem transports food by means of its sieve tubes both in the upward and downward directions.

Punjab State Board Life Processes Class 10 Science

Punjab State Board Life Processes Class 10 Science Question and Answers

Question 4. Give reason :

  1. Ventricles have thicker walls than the atria
  2. Capillaries have one-cell thick walls.

Answer:

  1. Atria receive blood from veins and pump the same in two adjacent ventricles. Ventricles have to pump blood forcefully in order to send it to different parts of the body.
  2. Capillaries are meant for the exchange of materials between tissue fluid and blood.

Question 5. How are O2 and CO2 transported in human beings?
Answer:

Both are transported through blood. Oxygen travels in a combined form with haemoglobin as oxyhaemoglobin. Carbon dioxide is transported both in plasma (77%) as well as combined with haemoglobin (23%).

Punjab State Board Life Processes Class 10 Science

Question 6.

  1. What is the role of fibrinogen?
  2. How is blood clotting useful?

Answer:

  1. Fibrinogen terms insoluble fibrin that polymerises and produces a network as the base of blood clots.
  2. It seals the place of injury in the blood vessel. As a result, blood loss from the injured blood vessel stops.

Question 7. What do you mean by double circulation? Why is it necessary?
Answer:

Double circulation

Double circulation is the passage of the same blood twice through the heart in order to complete one circulation. One step is the passage of deoxygenated blood from the right ventricle to the lungs and the return of oxygenated blood to the left auricle.

The second is the pumping of oxygenated blood to the rest of the body and the return of deoxygenated blood to the right auricle.

PSEB Class 10 Science Chapter 1 Life Processes Solutions

Importance.

  1. It provides for thorough oxygenation of the whole deoxygenated blood in the lungs.
  2. It ensures the supply of completely oxygenated blood to all body parts for their efficient working and thermoregulation.

Punjab State Board Question 8. List three kinds of blood vessels and their functions.
Answer:

Capillaries, arteries and veins.

Capillaries.

  1. Exchange of materials between blood and tissue fluid.
  2. Filtering out tissue fluid.
  3. Diapedesis for killing germs.

Artery,

  1. Supply of oxygenated blood to all body parts
  2. Sending deoxygenated blood to lungs for oxygenation

Veins.

  1. Carrying deoxygenated blood from various body parts to the heart.
  2. Carrying of oxygenated blood from lungs to heart.

Punjab State Board Life Processes Class 10 Science

Question 9.

  1. What is the composition of blood?
  2. How are oxygen and carbon dioxide transported in our bodies?

Answer:

  •  Composition of Blood. Plasma (55%) and blood cells (45%). Blood cells are of three types—erythrocytes, leucocytes and blood platelets.
  • Oxygen is transported as oxyhaemoglobin (97%) and a small quantity dissolved in plasma.
  • Carbon dioxide is transported as carbaminohaemoglobin (23%), bicarbonate (70%) and carbonic acid (7%) in plasma.

Life Processes Class 10 Question and Answers PSEB

Question 10. What is translocation? Why is it essential for plants? Where are the substances translocated by phloem delivered?
Answer:

Translocation

Translocation. It is the passage of food and other solutes from the region of their source to the region of their sink or utilisation.

  1. Requirement. Every cell requires food for its subsistence while food is available only from the region of manufacture and storage.
  2. Delivery. Though every cell requires food, the major areas of delivery of food materials are growing regions, growing fruits and storage regions.

Question 11. Explain why is transportation of materials is necessary in animals.
Answer:

Animals have specialised regions for digestion of food, exchange of gases and elimination of wastes.

  • However, every cell of the body requires food materials and oxygen. It also produces carbon dioxide and wastes.
  • Therefore, a transport system (blood circulatory system) is required to pick up nutrients from the digestive tract, oxygen from the lungs, and hormones from endocrine glands for supply to cells.
  • The transport system also collects carbon dioxide and wastes to take them to the lungs and kidneys.

Question 12. Give one function each of

  1. Blood vessels
  2. Lymph and
  3. Heart.

Answer:

  1.  Blood Vessels. Transport of blood from heart to body parts and back, exchange of materials between blood and tissue fluid in the region of capillaries.
  2. Lymph. It collects extra tissue fluid, secretions and excretions from the tissues for pouring into blood.
  3. Heart. It pumps oxygenated blood to different body parts and deoxygenates to the lungs.

PSEB Class 10 Biology Life Processes Notes

Question 13. Write three types of blood vessels. Give one important feature of each.
Answer:

Three types of blood vessels

The three types of blood vessels are capillaries, arteries and veins.

  1. Capillaries. Very fine tubes with walls made of single layers of cells. They are specialised in exchanging materials with tissue fluid.
  2. Arteries. They have thick elastic walls with narrow lumen. Arteries carry blood away from the heart. They usually possess oxygenated blood, except for pulmonary arteries.
  3. Veins. They have thin walls, and internal valves, with wide lumen carrying usually deoxygenated blood towards the heart, except pulmonary veins.

Question 14. Define the term transpiration. Design an experiment to demonstrate this process.
Answer:

Transpiration

Transpiration is the loss of water in vapour form from the aerial parts of the plants.

Experiment.

  1. Take a well-watered potted plant,
  2. Cover it shoot system with a transparent polythene sheet. Tie the edges of the sheet properly with thread.
  3. Place the apparatus in bright sunlight for 30-45 minutes,
  4. Observe the appearance of water droplets on the inner side of the polythene covering,
  5. Apparently, the shoot has lost water in vapour form which has condensed.

Question 15. What is transpiration? List its two functions.
Answer:

Transpiration. It is the loss of water in vapour form from the aerial parts of the plants.

Functions.

  1. Transpiration creates a force for absorption and ascent of water.
  2. It prevents overheating of plants exposed to strong sunlight.

Question 16. List two types of transport systems in human beings and write the functions of any one of them.
Answer:

Blood circulatory system and lymphatic system.

Functions of Blood Circulatory System.

  1. Transport of oxygen.
  2. Transport of carbon dioxide.
  3. Transport of digested food.
  4. Transport of waste products.
  5. Transport of hormones.
  6. Transport of salts.
  7. Plugging place of injury.
  8. Protection from pathogens.

Functions of Lymphatic System.

  1.  Transport of digested fat from the intestine and later passage into the blood.
  2. It maintains blood volume by draining extra tissue fluid and passing it into the blood.

Punjab Board Class 10 Science Chapter 1 Solutions

Question 17. List four functions of the human heart. Why is double circulation necessary in the human body?
Answer:

Functions of Heart.

  1.  Receiving deoxygenated blood from various parts of the body in the right auricle.
  2. Pumping the deoxygenated blood into the lungs for oxygenation.
  3. Receiving oxygenated blood from lungs in left auricle.
  4. Pumping the oxygenated blood to all parts of the body.

Double Circulation. It is the passage of the same blood twice through the heart, once for complete oxygenation and afterwards supply of pure oxygenated blood to all parts human of the body. It meets the high energy requirement of the body for thermoregulation and high activity.

Question 18. What is haemoglobin? State the consequences of deficiency of haemoglobin in our bodies.
Answer:

Haemoglobin

  1. Haemoglobin is a respiratory pigment of the body. It is present inside the red blood corpuscles. Haemoglobin combines with oxygen to form oxyhaemoglobin. As oxyhaemoglobin, it reaches all parts of the body.
  2. Oxygen separates from haemoglobin and diffuses into the tissue fluid and then into living cells where it is being consumed in respiration. Haemoglobin also carries a smaller amount of carbon dioxide from tissues to the lungs.
  3. Deficiency. A deficiency of haemoglobin, also called anaemia results in less supply of oxygen to tissues that produce lesser energy so that all activities of the body slow down.

Class 11 Chemistry Classification of Elements and Periodicity in Properties Question and Answers

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Class 11 Chemistry Classification of Elements and Periodicity in Properties Question and Answers

Question 1. Mention two laws (for the classification of elements), which were proposed before Mendeleev?
Answer:

Dobereincr’s law of triads and Newland’s law of octaves.

Question 2. Write the 11JPAC name and the symbol of the element with atomic number 108.
Answer:

Unniloctium; Uno.

Question 3. What are the names given to eka-aluminum and cka-silicon predicted by Mendeleev?
Answer:

The names of these elements are Gallium and Germanium respectively.

Read And Learn More Class 11 Chemistry Solutions

Question 4. Mention the number of periods and groups in the long form of the periodic tabs.
Answer:

7 periods and 18 groups

Class 11 Chemistry Classification of Elements and Periodicity in Properties Question and Answers

Question 5. Mention the name of the s -block element which is placed along with the p -block elements.
Answer:

Helium (He, Is2).

Class 10 ScienceClass 11 Chemistry
Class 11 ChemistryTransformation of Sentences
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Question 6. To which group of the long form of the periodic table do the chalcogens belong?
Answer:

The chalcogens belong to group 16.

Class 11 Chemistry Classification of Elements and Periodicity in Properties

Question 7. Write the general electronic configuration of the inner- [transition elements.
Answer:

⇒ \((n-2) f^{1-14}(n-1) d^{0-1} n s^2 \text {. }\)

Question 8. Write the atomic number of the element placed just below cobalt (Z = 27) in the modern periodic table
Answer:

The atomic number of the element is 27 + 18 = 45.

Question 9. Indicate the position of the element having electronic configuration Is22sz2p63s23p63d34s2 in the periodic table.
Answer:

4th period and 15th group in the periodic table

Question 10. What is the total number of elements incorporated now in the periodic table? Write down the name and symbol of the last element.
Answer:

The total number of elements incorporated in the periodic table is 118. The name of the last element is Ununoctium and its symbol is Uuo (Z = 118).

Question 11. Which group of the periodic table contains solid, liquid & gaseous elements? What are those elements?
Answer:

Solid, liquid, and gaseous elements are present in group- 17(VIIA). These elements are fluorine (gas), chlorine (gas), bromine (liquid), iodine (solid) and astatine (solid).

Question 12. Which element is the most electronegative
Answer:

Fluorine is the most electronegative of all the elements.

Question 13. Name one property that is not periodic
Answer:

The radioactivity of an element is not a periodic property.

Question 14. Arrange according to the instructions given in the bracket:

  • O, Te, Se, S (Increasing order of electronegativity)
  • Na, Cu, Zn (Increasing order of electropositive character)
  • I, F, Br, CI (Increasing order of metallic character)
  • I, F, Br, Cl (Decreasing order of electron affinity)
  • Na, K, F, Cl, Br (Increasing order of atomic radius)
  • Mg, AI, Si, Na (Increasing order of ionization potential)
  • PbO, MgO, ZnO (increasing order of basic character)
  • Na+, Mg2+, Al3+ (Decreasing order of size)
  • Cu, S, C (graphite) (Increasing order of electrical conductivity)
  • Be, C, B, N, 0 (Increasing order of electron affinity)
  • Cl, Mg, C, S (Increasing order of electronegativity)
  • A1203, P205, CI207, S03 (Increasing order of acidic property)
  • MgO, ZnO, CaO, Na20, CuO (Increasing order of basic property)
  • Na+, F-, O2-, Mg2+, N3- (Increasing order of ionic radii)
  • B —Cl, Ba—Cl, Br —Cl, Cl —Cl (Increasing order of bond polarity)
  • Br, F, Cl, I (Increasing order of oxidizing property)
  • Na, Cs, K, Rb, Li (Increasing order of atomic volume)
  • Sb203, N20g, AS203 (Increasing order of acidic property)

Answer:

  • Te < Se < S < O
  • Cu< Zn< Na
  • F < Cl < Br <I
  • Cl > F > Br >I
  • F < Cl < Br < Na < K
  • Na<Al<Mg<Si
  • ZnO < PbO < MgO
  • Na+ > Mg2+ > Al3+
  • S < C(graphite) <Cu
  • Be<N<B<C<0
  • Mg < C = S < Cl
  • A1203 < P205 < S03 < C1207
  • CuO < ZnO < MgO < CaO < Na20
  • Mg2+ < Na+ < F- < 02- < N3-
  • Ba —Cl > B —Cl > Br —Cl > Cl —Cl
  • I < Br < Cl < F
  • Li < Na < K < Kb < Cs
  • Sb203 < AS203 < N205

Class 11 Chemistry Classification of Elements and Periodicity in Properties

Question 15. Name the elements having the highest and lowest ionization enthalpy.
Answer:

Highest value: Helium (He), Lowest value: Cesium (Cs).

Question 16. What do you mean by the statement—the covalent radius of H-atom is 0.37 A?
Answer:

It indicates that one-half of the internuclear distance between two bonded H-atoms in an H2 molecule is 0.37 A.

Question 17. Indicate the similarity observed in the electron-gain enthalpy values of Mg and N.
Answer:

Both Mg and N have positive electron-gain enthalpy values.

Question 18. Why is the size of F- smaller than that of O2- ion? {
Answer:

O2- and F- ions are isoelectronic, but their nuclei contain 8 and 9 protons respectively.

So, the nuclear attractive force acting on the electrons of the F- ion is greater than that on the electrons of the O2- ion. Consequently, the F- ion is smaller than the O2- ion.

Question 19. Compare the radii of K+ and Cl- ions (each contain the same number of electrons)
Answer:

The nuclei of the isoelectronic ions K+ and Cl- contain 19 and 17 protons respectively. So the magnitude of nuclear attractive force acting on the electrons of K+ ions is greater than that on the electrons of Cl- ion. Consequently, the radius of the K+ ion is smaller than that of the Cl- ion.

Question 20. What do you understand by a negative value of electron-gain enthalpy of an element?
Answer:

Negative value of electron-gain enthalpy of an element

It signifies that energy is released when an isolated gaseous atom of the element under consideration accepts an electron to form a monovalent gaseous anion.

Question 21. The electronic configuration of the atom of an element is ls22s22p63s23px. Locate its position in the periodic table. Is it a metal or non-metal? What is its valency?
Answer:

The atonibre receives its last electron in 3p -orbital. So it belongs to p -block elements. Accordingly, its group number = 10 + no. of electrons in the valence shell = 10 + (2 + 1)= 13.

Again, the period of the element = several principal quantum numbers ofthe valence shell = 3.

It is a metal because it belongs to the 13th group of the periodic table. Valency of the element = number of electrons in the valence shell =2+1 = 3.

Question 22. The atomic numbers of elements A, B, and C are 10, 13, & 17 respectively. Write their electronic configurations. Which one of them will form a cation and which one an anion? Mention their valencies.
Answer:

Electronic configuration of 10A: ls22s22p6 electronic configuration of 13B: ls22s22p63s23p1

Electronic configuration of 17C: ls22s22p63s23p5

The element, A belonging to group 18, is an inert gas.

So it will form neither a cation nor an anion. The element B, belonging to group 13, is a metal. It will readily form a cation by the loss of 3 electrons from its valence shell (3rd shell).

The element C will readily gain one electron in its outermost 3rd shell to attain inert gas electronic configuration (Is2……3s23p6). So, C will form an anion.

Valency of A = 0 (it has a complete octet of electrons in the outermost shell). Valency of B = 3 (by the loss of 3 electrons from the 3rd shell it will attain stable inert gas electronic configuration).

Valency of C = 1 (because by the gain of the electron, it can attain stable inert gas configuration).

Class 11 Chemistry Chapter 3 Questions and Answers

Question 23. A, B, and C are three elements with atomic numbers group (8 + 2) = 10. 17, 18, and 20 respectively. Write their electronic configuration. Which one of them is a metal and which one is a non-metal? What will be the formula of the compound formed by the union of A and C? What may be the nature of valency involved in the formation of the above compound?
Answer:

Electronic configuration of 1A: ls22s22p63s23p5

Electronic configuration of 10B: ls22s22p63s23p6

Electronic configuration of 2QC: ls22s22p63s23p64s2

Element C is a metal as it can easily form a dipositive ion by the loss of two electrons from 4s -orbital. ElementA is a non-metal as it can achieve inert gas configuration by accepting one electron in a 3p -subshell.

As already mentioned, the element C can easily, form a dipositive cation (C2+), while the element A readily forms a uninegative anion (A-).

So the elements A and C can combine to form the compound CA2.

The above-mentioned compound is electrovalent because it will be formed by the union of two A-ions with one C2+ ion.

Question 24. Outer electronic configuration of 4 elements are as given below follows: 3d°4s1 3s23p5 4s24p6 Electronic configuration of 10A: ls22s22p6 3d84s2. Find their positions in the periodic table
Answer:

This element (3d°4s1) is an s -block element. So it is an element of the 4th period in group-1.

This element (3s23p5) is a p -block element containing (2 + 5) or 7 electrons in the valence shell (n = 3). Soitis an element ofthe 3rd periodin group (10 + 2 + 5) = 17.

This element (4s24p6) is a p -block element containing (2 + 6) or 8 electrons in the valence shell (n = 4). So it is an element of the 4th period in group (10 + 2 + 6) = 18.

This element (3d84s2) is a d -block element containing 8 electrons in the d -orbital of the penultimate shell (n = 3) and 2 electrons in s -the orbital of the valence shell (n = 4). So, it is an element of the 4th period in group (8+2)=10

Question 25. Write the electronic configuration of the element with atomic number 35. What will be the stable oxidation states of the element?
Answer:

Electronic configuration: ls22s22p63s23p63d104s24p5. The most stable oxidation state is -1 because it can accept one electron to achieve inert gas configuration (Is2… 3d104s24p6).

Again in an excited state, it can also exhibit oxidation numbers +3 or +5 by forming a covalent bond by using its 3 or 5 odd electrons in its outermost shell.

image-

Question 26. justify by mentioning two reasons, the inclusion ofCa and Mgin the same group of the periodic table.
Answer:

Both Ca and Mg have similar electronic configurations. Both of them belong to s -block.

Electronic configuration of Mg: ls22s22p63s2 Electronic configuration of Ca: ls22s22p63s23p64s2

Both are typical divalent metals and form stable ionic compounds, e.g., MgCl2, CaCI2; MgO, CaO.

Question 27. Cu, Ag & Au are regarded as transition elements. Why?
Answer:

Despite having filled d -orbitals (d10), copper, silver, and gold are considered transition elements because at least in one stable oxidation state of the atoms of these elements, d -orbital is partially filled with electrons, For example, the electronic configuration of Cu2+ is ls22s22p63s23p63d94s°.

Question 28. Write down electronic configuration of the element having atomic number 21. Name two other elements of the same series to which this element belongs. Why do they belong to the same series?
Answer:

Electronic configuration ofthe element (Atomicnumber= 21): ls22s22p63s23p63d14s2 From the electronic configuration, it can be said that the element belongs to the first transition series as its 3d -orbital is partially filled. Two other elements belonging to this series are Cr(24) and Mn(25). The 3d -orbitals of these elements are also partially filled.

Their electronic configurations are—

  1. Cr: ls22s22p63s23p63d54s1
  2. Mn: ls22s22p63s23p63d54s2

Class 11 Chemistry Chapter 3 Questions and Answers

Question 29. Can Cu (At. no. 29) and Zn (At. no. 30) be called transition elements? Explain.
Answer:

Although the Cu -atom in its ground state does not contain an incompletely filled d-orbital, Cu2+ has a partially filled d-orbital and so it is a transition element.

Electronic config. of Cu: ls22s22p63s23p63d104s1

Electronic config. of Cu2+: ls22s22p63s23p63d94s°

In the ground state orin any stable oxidation state of Zn, the d orbital is filled. So,it is not a transition element.

Electronic config. of Zn: |lsÿ2$22p63s23p63d104s2

Electron Config. of Zn: 2’tI?lls22sÿ2p63s23p63d104s0

Question 30. The atomic numbers of three elements A, B, and C are 9, 13, and 17 respectively.

  1. Write their electronic configuration.
  2. Ascertain their positions in the periodic table.
  3. Which one is most electropositive and which one is most electronegative?

Answer: Electronic configurations of gA: ls22s22p5, 13B: ls22s22p63s23p1, 17C: ls22s22p63s23p5

All three elements are p -block elements. Hence, their group and period numbers are as follows:

Question 27. Cu, Ag & Au are regarded as transition elements. Why?
Answer:

Despite having filled d -d-orbitals (d10), copper, silver, and gold are considered transition elements because at least in one stable oxidation state of the atoms of
these elements, the -orbital is partially filled with electrons, For example, the electronic configuration of Cu2+ is ls22s22p63s23p63d94s°.

Question 28. Write down the electronic configuration of the element having atomic number 21. Name two other elements of the same series to which this element belongs. Why do they belong to the same series?
Answer:

Electronic configuration ofthe element (Atomicnumber= 21): ls22s22p63s23p63d14s2

From the electronic configuration, it can be said that the element belongs to the first transition series as its 3d-orbital is partially filled.

Two other elements belonging to this series are Cr(24) and Mn(25). The 3d -orbitals of these elements are also partially filled.

Their electronic configurations are—

  1. Cr: ls22s22p63s23p63d54s1
  2. Mn: ls22s22p63s23p63d54s2

Question 29. Can Cu (At. no. 29) and Zn (At. no. 30) be called transition elements? Explain.
Answer:

Although the Cu -atom in its ground state does not contain an incompletely filled d-orbital cu2+ has a partially filled d-orbital and so it is a transition element.

Electronic config. of Zn: sÿ2s22p63s23p63d104s2

Electron Config. of Zn2+: lls22sÿ2p63s23p63d104s0

 

Question 30. The atomic numbers of three elements A, B, and C are 9, 13, and 17 respectively. Write their electronic configuration. Ascertain their positions in the periodic table. Which one is most electropositive and which one is most electronegative?
Answer:

Electronic configurations of gA: ls22s22p5, 13B: ls22s22p63s23p1, 17C: ls22s22p63s23p5

Periodicity in Properties Class 11 Chemistry Solutions

All three elements are p -block elements. Hence, their group and period numbers are as follows:

table-

Element B can easily donate 3 electrons from its outermost shell to attain a stable inert gas configuration. So, it is the most electropositive element.

Elements A and C are electronegative because they can accept one electron to attain a stable inert gas electronic configuration.

These elements (A and C) have similar outer electronic configurations (ns2np5) but the size of A is smaller than that of C. So, the electronegativity of A is greater than that of C. Hence, A is the most electronegative element.

Question 31. Why is the atomic size of Ca2+ smaller than that of K+?
Answer:

K+ and Ca2+ are isoelectronic (each contains 18 electrons). K+ contains 18 protons in its nucleus and Ca2+ contains 20 protons.

Number of protons being in the Ca2+ ion, the electrons in the outermost shell of the Ca2+ ion will experience greater attractive force by the nucleus compared to K+. Consequently, Ca2+ has a smaller ionic size than K+ ions.

Question 32. The atomic radius of a chlorine atom is 0.99 A but the ionic radius of chloride (Cl-) is 1.81 A—explain.
Answer:

In an anion, the total number of electrons being greater than that of the number of protons, attraction of the nucleus for the outermost electrons decreases.

Furthermore, due to mutual repulsion among electrons, the outermost orbit gets appreciably expanded.

As a result, the anionic radius becomes more than the radius of the parent atom. On account of this, the radius of Cl- (1.81 A) (18 electrons and 17 protons) is greater than the radius ofchlorine (0.99 A) atom (17 electrons and 17 protons).

Question First ionization energy of elements increases with atomic numbers of the elements in a period—why? Cite an exception.
Answer:

In any period, with an increase in atomicnumber, the magnitude of the positive charge of the nucleus increases, but there is no addition of any new shell.

In consequence, the attractive force of the nucleus for the outermost electrons increases. So, the amount of energy required for the removal of an electron from the outermost shell of the atom (z.e., first ionization energy) in any period increases with the increase in atomic number.

An exception to this generalization is the nitrogen-oxygen pair. In the second period, oxygen belonging to group VIA has a lower value of first ionization energy than nitrogen of group. The reason can be ascribed to the stable electronic configuration of the nitrogen atom (ls22s22p3)

Question 34. The ionization potential of O is less than that of N— explain.
Answer:

The ionization potential of O is less than that of N

The reason for such a difference may be explained on the basis oftheir electronic configurations filled, its electronic configuration is highly stable.

So, a large amount of energy is required to form an N+ ion by the removal of a 2pelectron.

On the other hand, the formation of 0+ ion by removal of one electron from a partially filled 2p -orbital requires less energy, since the 2p -orbital of 0+ion is half-filled, the electronic configuration assumes stability. Hence, oxygen has a lower ionization potential than nitrogen.

Periodicity in Properties Class 11 Chemistry Solutions

Question 35. Explain why the ionization potentials of inert gas are very high while that of alkali metals are very low. ses are
Answer:

Outermost shells of inert gases contain octets of electrons. Besides this, each of the inner shells of inert gas elements is filled.

Such configuration is exceptionally state conversion of a neutral inert gas atom into its ions try removal of an electron from the outermost shell requires large energy. As a result, they have high ionization potentials.

Configuration of the outermost and penultimate shell of alkali metals is {n-l)s2(n-1)p6nsl (except Li ).

Thus the loss of 1 electron from their outermost shell brings about a stable configuration of inert gases. Hence, the conversion of alkali metals to their ions requires comparatively less amount of energy. As a result, alkali metals have low values of ionization potential.

Question 36. Which member in each of the following pairs has a lower value of ionization potential? F, Cl S, Cl Ar, K O Kr, Xe Na, Na+.
Answer:

Cl has lower ionization enthalpy than F because electrons of 2p-orbital in F are more strongly attracted by the nucleus than the 3p-electrons in Cl.

(Note that effective nuclear charge on the outermost electrons is nearly the same for both and Cl).

S has lower ionization enthalpy than Cl because the size of S is greater than that of Cl and also the nuclear charge of S is less than that of CL

K has a lower ionization potential than Ar as the outermost shell is filled with electrons in Ar. On the other hand, K can attain a stable configuration like the inert gas Arby with the loss of only an electron.

Xe has lower ionization enthalpy than Kr because ionization enthalpy decreases on moving down a group in the periodic table.

Na (ls22s22p63s1) has lower ionization enthalpy’ than Na+(ls22s22p6), because the former can attain inert gas-like electronic configuration by loss of 1 electron from its outermost shell, whereas the latter attains unstable electronic configuration (Is22s22p5) by loss of one electron from its outermost shell.

Question 37. Why is the value of electron-gain enthalpy negative?
Answer:

When an electron is added to a neutral gaseous atom to form a negative gaseous ion, energy’ is usually liberated, i.e., the enthalpy change in the process is usually negative. So
electron-gain enthalpies of most elements have negative values.

Question 38. Calculate the energy (in kj unit) required to convert all sodium atoms into sodium ions, present in 3.45 mg of its vapor. [I.P of sodium 490kJ mol-1 ]
Answer:

Sodium atoms present \(=\frac{3.45}{23} \times 10^{-3}=1.5 \times 10^{-4} \mathrm{~mol}\)

Na(g) + = Na+(g) + e;I = 490 kj. mol-1.

The energy required for the ionization of 1 mol sodium is 490 kj.

The energy required for ionization of 1.5 X 10-4 mol sodium is 490 X 1.5 X 10-4 kj = 73.5J

Question 39. A, B, C, and D are four elements of the same period, of which A and B belong to s -block. B and D react together to form B+D-. C and D unite together to produce a covalent compound, CD2. What is the formula of the compound formed by A and D ? 0 What is the nature of that compound? What will be the formula and nature of the compound formed by the union of B and C
Answer:

Since A and B are s -block elements of the same period, one of them is an alkali metal of group IIA while the other is an alkaline earth metal of group IIA.

B and D react to form anionic compound B+D. Therefore, B is a monovalent alkali metal of group IA, and D is a monovalent electronegative element of group VIIA.

Hence, the other element A of the s -the block is a bivalent alkaline earth metal of group-IIA. C and D combine to produce the covalent compound CD2. Hence, C is a bivalent electronegative element belonging to group VIA.

The formula of the compound formed by the combination of electropositive bivalent element A with electronegative monovalent element D is AD2

The compound is ionic or electro valent in nature.

A compound formed by reactions of electropositive monovalent element B with electronegative bivalent element C will have the formula B2C. It is an electrovalent or ionic compound.

Periodicity in Properties Class 11 Chemistry Solutions

Question 40. What changes in the following properties are observed while moving from left to right along a period & from top to bottom in a group? Atomic volume, Valency, Electronegativity, Oxidising, and reducing powers.
Answer:

On moving from left to right across a period, atomic volume first decreases and then increases. In a group, atomic volume increases with an increase in atomic number down a group.

Oxygen-based valency goes on increasing from left to right over a period but does not suffer any change down a group.

Electronegativity increases gradually from left to right across a period while it decreases down a group with an increase in atomic number.

Oxidizing power increases from left to right across a period and decreases from top to bottom in a group.

On the other hand, reducing power decreases from left to right in a period but it increases from top to bottom in a group.

 

PSEB 11th Class Biology Kingdom Monera Multiple Choice Questions

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Kingdom Monera Multiple Choice Questions

Question 1. From competitive examinations

Find out the comet match:

  1. Aids- bacillus anthesis
  2. Syphilis- treponema pallidum
  3. Gonorrhea- Leishmania donovani
  4. Urethritis- enthameaobea gingivalis

Answer: 2. Aids- bacillus anthesis

Question 2. Bt gene occurs in

  1. Bacillius thurigensis
  2. Escherichia coli
  3. Agrobacterium tumefaciens
  4. Rhixobium leguminosarum

Answer: 1. Bacillius thurigensis

Question 3. In which bacterial reproduction phage lake part?

  1. Conjugation
  2. Transformation
  3. Binary fission
  4. Transduction.

Answer: 4. Transduction.

Read And Learn More Class 11 Biology MCQs

Question 4. Mvcoplasmas arc not sensitive to :

  1. Penicillin
  2. Streptomycin
  3. Erythromycin
  4. Neomycin.

Answer: 1. Penicillin

PSEB 11th Class Biology Kingdom Monera MCQs

PSEB 11th Class Biology Kingdom Monera Multiple Choice Questions

Question 5. Mitotic apparatus is absent in:

  1. Green algae
  2. Fungi
  3. Bacteria
  4. Higher plants.

Answer: 3. Bacteria

Question 6. Teichoic acid is present in the cell wall of:

  1. Bacteriophage
  2. Mycoplasma
  3. Nostoc
  4. Pneumococcus.

Answer: 4. Pneumococcus.

Question 7. Disease pneumonia is due to:

  1. Virus
  2. Bacterium
  3. Cyanobacterium
  4. Protozoan.

Answer: 2. Bacterium

Question 8. Bacteria cannot survive in highly salted pickles because:

  1. Bacteria do not get light for photosynthesis
  2. The pickle does not contain nutrients necessary for bacteria to live
  3. Salt inhibits reproduction
  4. Bacteria get plasmolysed and thus killed.

Answer: 4. Bacteria get plasmolysed and thus killed.

Question 9. A non-legume, symbiotic nitrogen-fixing bacterium is:

  1. Rhizobium
  2. Azotobacter
  3. Frankia
  4. Clostridium.

Answer: 3. Frankia

Question 10. What is true for photolithotrophs?

  1. Obtain energy from radiations and hydrogen from organic compounds
  2. Obtain energy from radiations and hydrogen from inorganic compounds
  3. Obtain energy from organic compounds
  4. Obtain energy from inorganic compounds.

Answer: 2. Obtain energy from radiations and hydrogen from inorganic compounds

Question 11. The difference in gram + ve and gram – ve bacteria is due to:

  1. Cell wall
  2. Cell membrane
  3. Ribosome
  4. Cytoplasm.

Answer: 1. Cell wall

Question 12. What is true for archaebacteria?

  1. All halophiles
  2. All photosynthetic
  3. All fossils
  4. Oldest living beings

Answer: 4. Oldest living beings

Question 13. Which of the following is not produced by in the lactose medium?

  1. Thiognlnclosidc transacetylase
  2. Lactose dehydrogenase
  3. Lactose permease
  4. I-galactosidase.

Answer: 2. Lactose dehydrogenase

Kingdom Monera Multiple Choice Questions PSEB Class 11

Question 14. The cell wall of a bacterium is composed of:

  1. Cellulose
  2. Chitinous
  3. Cellulose
  4. Chitin
  5. Mureill.

Answer: 4. Mureill.

Question 15. Plasmids occur in-

  1. Chromosomes
  2. Viruses
  3. Bacteria
  4. Chloroplasts.

Answer: 3. Bacteria

Question 18. Milk is changed into curd by:

  1. Acetobacter acetic
  2. Bailius megatherium
  3. Xanthomonas citri
  4. None.

Answer: 4. None.

Question 19. Match the names of antibiotics listed under column 1 with their sources given under column 2. Select the correct alphabet of two columns:

Kingdom Monera Question 16 Match the terms

  1. A—p, b—r, c—s, d—q
  2. A—r, b—p, c—s, d—q
  3. A—s, b—p, c—r, d—q
  4. A—r, b—s, c—p, d—q.

Answer: 4. A—r, b—s, c—p, d—q.

Question 17. Which one of the following organisms may respire in the absence of oxygen?

  1. Azotobacter
  2. Clostridium
  3. Rhizobium
  4. Lactobacillus.

Answer: 2. Clostridium

Question 18. Milk is changed into cured by

  1. Acetobacter aceti
  2. Bacillus megatherium
  3. Xanthomonas citri
  4. None.

Answer: 4. None.

Kingdom Monera Multiple Choice Questions PSEB Class 11

Question 19. Bacteria prepare food by oxidation of:

  1. N2
  2. N03
  3. Oxygen
  4. Glycogen.

Answer: 4. Glycogen.

Question 20. Extrachromosomal material of bacteria is found in:

  1. Circular dna
  2. Extrachromosomal dna
  3. Chromosomal dna
  4. Plasmid.

Answer: 4. Plasmid.

Question 23. Which of the following is correct?

  1. Diatoms produce basodiopores
  2. Hererocycytes occur in Boston
  3. Fronds develop in bryophtes
  4. Multiciliates sperms occur in angiosperms

Answer: 2. Hererocycytes occur in Boston

Question 24. Mnrein does not occur in the wall of :

  1. Diatoms
  2. Nostoc
  3. Eubacteria
  4. Blue-green algae.

Answer: 1. Diatoms

Question 25. Bacterial flagella are made up of

  1. Chlorine
  2. Fluorine
  3. Iodine
  4. Bromine.

Answer: 1. Chlorine

Question 26. Bacterial flagella are made up of :

  1. Protein
  2. Amines
  3. Lipids
  4. Carbohydrates.

Answer: 1. Protein

Question 27. Bacterium pseudomonas is useful as it can :

  1. Transfer genes from one plant to another
  2. Fix atmospheric nitrogen
  3. Produce several antibiotics
  4. Decompose a variety of organic compounds.

Answer: 2. Fix atmospheric nitrogen

Question 28. Bacterial ribosomes are :

  1. 70S
  2. 60 S
  3. 80 S
  4. 50 S.

Answer: 1. 70S

Question 29. The iron-chelating substance is produced by a growth-promoting rhizobacterium:

  1. Rhizobium japonicum
  2. Azospirillium
  3. Pseudomonas putida
  4. Aspergillus.

Answer: 2. Azospirillium

PSEB Class 11 Biology Chapter Kingdom Monera MCQs

Question 30. Which one is not correctly matched :

  1. Streptomyces—antibiotic
  2. Serratia—drug addiction
  3. Rhizobium—biofertilizer
  4. Spirulina—single cell protein.

Answer: 2. Serratia—drug addiction

Question 31. Azolla has a symbiotic relationship with :

  1. Chlorella
  2. Anabaena
  3. Nostoc
  4. Tolypothrix.

Answer: 2. Anabaena

Question 32. The best well-studied batching-plant relationship is that of:

  1. Cymmbactcrinl symbiosis with some aquatic ferns
  2. Modulation in snbanla stem
  3. Tiall formation by ay, what Merriam
  4. Growth stimulation by phosphate bacteria.

Answer: 3. Tiall formation by ay, what Merriam

Question 33. Auxosporcs and oocysts are formed respectively by

  1. Several diatoms and a few cyanobacteria
  2. Several cyanobacteria and several diatoms
  3. Some diatoms and several cyanobacteria
  4. Some cyanobacteria and many diatoms.

Answer: 1. Several diatoms and a few cyanobacteria

Question 34. Barophilic prokaryotes:

  1. Grow slowly in highly alkaline frozen lakes at high altitudes
  2. Occur in water containing high concentrations of barium hydroxide
  3. Grow and multiply in very deep marine sediments
  4. Readily grow and divide in seawater enriched in any soluble salt of barium.

Answer: 1. Grow slowly in highly alkaline frozen lakes at high altitudes

Question 35. For retting of jute, the fermenting microbe used is:

  1. Helicobacter pylori
  2. Mesophilic bacteria
  3. Streptococcus lactis
  4. Butyric acid bacteria.

Answer: 4. Butyric acid bacteria.

Question 36. Gram-ve bacteria possess peptidoglycan and an extra layer of:

  1. Protein
  2. Lipoprotein
  3. Lipopolysaccharide
  4. Lipid.

Answer: 3. Lipopolysaccharide

PSEB Class 11 Biology Chapter Kingdom Monera MCQs

Question 37. Which of the following is a pathogenic bacterium of the colon

  1. Balantidium coli
  2. Entamoeba coli
  3. Enterobium vermicularis
  4. Escherichia coli.

Answer: 4. Escherichia coli.

Question 38. Nitrogen-fixing bacteria are associated with

  1. Malvaceae
  2. Gramineae
  3. Cruciferae
  4. Leguminasae

Answer: 4. Leguminasae

Question 39. Which of the following contain polyhedral bodies?

  1. Bacteria
  2. Nostoc
  3. Mycoplasma
  4. None of the above.

Answer: 2. Nostoc

Question 40. Inoculation against malaria is out of the question because:

  1. It does not produce antibodies and antitoxins
  2. Plasmodium produce antitoxins
  3. Plasmodium produces minute bodies
  4. None of the above.

Answer: 1. It does not produce antibodies and antitoxins

Question 41. Bacteria are considered plants because they :

  1. Have chlorophyll
  2. Have stomata
  3. Have rigid cell walls that are green in color

Answer: 3. Have rigid cell walls that are green in color

Question 42. Curing olten leaves is brought about by the activity of:

  1. Viruses
  2. Fungi
  3. Bacteria
  4. Myconhizn

Answer: 3. Bacteria

Question 43. In prokaryotes. Chromatophotvs atv

  1. Specialized granules responsible for the coloration of cells
  2. Structure is responsible for organizing the shape of (be organism
  3. Inclusion bodies lying five inside the cells for carrying out various metabolic activities
  4. Internal membrane systems that may become extensive and complex in photosynthetic bacteria

Answer: 4. Internal membrane systems that may become extensive and complex in photosynthctic bacteria.

Question 44. Which of the following is a flowering plant with modules containing filamentous nitrogen-fixing microorganisms?

  1. Crotalaria juncea
  2. Cycos revoluta
  3. Ciccr arietinwn
  4. Casuarina equisetifolia.

Answer: 4. Casuarina equisetifolia.

Question 45. Which one of the following statements is correct?

  1. Both azotobacter and rhizobium fix atmospheric nitrogen in root nodules of plants.
  2. Cyanobacteria such as anabasine and nostoc are important mobilizers of phosphates and potassium for plant nutrition in the soil.
  3. At present it is not possible to grow maize without chemical fertilizers.
  4. Extensive use of chemical fertilizers may lead to eutrophication of nearby water bodies.

Answer: 4. Extensive use of chemical fertilizers may lead to eutrophication of nearby water bodies.

Question 46. Which one of the following statements about mycoplasma is wrong?

  1. They are pleomorphic
  2. They are sensitive to penicillin
  3. They cause diseases in plants
  4. They are also called people.

Answer: 2. They are sensitive to penicillin

Question 47. Which one of the following is an example of a negative feedback loop in humans

  1. Secretion of tears alters the falling of sand particles into the eye.
  2. Salivation of the mouth at the sight of delicious food.
  3. Secretion of sweat glands and constriction of skin blood vessels when it is too hot.
  4. Constriction of skin blood vessels and contraction of skeletal muscles when it is too cold.

Answer: 4. Constriction of skin blood vessels and contraction of skeletal muscles when it is too cold.

PSEB Class 11 Biology Chapter Kingdom Monera MCQs

Question 48. In the light of recent classification of living organisms into three domains of life (bacteria, archaea, and eukarya), which one of the following statements is true about archaea?

  1. Archaca completely differs from both prokaryotes and eukaryotes
  2. Archaea completely differ from prokaryotes
  3. Archaea resemble eukarya in all respects
  4. Archaea have some novel features that are absent in other prokaryotes and eukaryotes.

Answer: 4. Archaea have some novel features that are absent in other prokaryotes and eukaryotes.

Question 49. Organisms called methanogens are most abundant in a :

  1. Sulfur rock
  2. Cattle yard
  3. Polluted stream
  4. Hot spring.

Answer: 2. Cattle yard

Question 50. Besides paddy fields, cyanobacteria are also found inside the vegetative part of :

  1. Cycas
  2. Equisetum
  3. Psilotum
  4. Pinus

Answer: 1. Cycas

Question 51. Which of the following are likely to be present in deep sea water?

  1. Eubacteria
  2. Blue-green algae
  3. Saprophytic fungi
  4. Archaebacteria

Answer: 4. Archaebacteria

PSEB Class 11 Biology Sense Organs Multiple Choice Question and Answers

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Sense Organs Multiple Choice Question and Answers

Question 1. Taste Buds Of The Interior Stile Of Longue In Humans Can Detect:

  1. Sour Taste
  2. Bitter Taste
  3. Sweet Taste
  4. Saltish Taste.

Answer: 2.

Question 2. Anterior Irregular Wavy Part Of the Retina Is :

  1. Ora Serrata
  2. Pars Optica
  3. Ocular Conjunctiva
  4. Fovea Centralis.

Answer: 1.

Question 3. Structure That Provides Balance To The Body Is Located In

  1. Outer Ear
  2. Middle Ear
  3. Inner Ear
  4. Eustachian Tubes.

Answer: 3. Inner Ear

Question 4. When We Migrate From Dark To Light, We Fail To See For Some Time, But After A Time Visibility Becomes Normal. It Is an Example Of the:

  1. Accommodation
  2. Adaptation
  3. Mutation
  4. Photoperiodism.

Answer: 2. Adaptation

Read And Learn More Class 11 Biology MCQs

PSEB Class 11 Biology Sense Organs Multiple Choice Question and Answers

Question 5. Characteristic Character Of Human Comea :

  1. Secreted By Conjunctiva And Glandular
  2. It Is Lacrimal Gland that secretes Tears
  3. Blood Circulation Is Absent In Cornea
  4. In Old Age, It Becomes Hardened And White Layer Deposits On It Which Causes The Cataract.

Answer: 3. Blood Circulation Is Absent In Cornea

Question 6. The Arrangement Of Ear Ossicles In Mammalian Ear Is

  1. Stapes, Malleus, Incus
  2. Malleus, Incus, Stapes
  3. Incus, Malleus, Stapes
  4. Columella, Malleus, Incus.

Answer: 2. Malleus, Incus, Stapes

PSEB Class 11 Biology Sense Organs MCQs

Question 7. Opacity Of The Lens In The Eyes Leads To :

  1. Cataract
  2. Presbyopia
  3. Astigmatism
  4. Hyperopia.

Answer: 1. Cataract

Question 8. The Thinnest Skin Is Present On The :

  1. Eyelids
  2. Soles Of Feet
  3. Back Of The Hand
  4. Forehead.

Answer: 1. Eyelids

Question 9. Which Of The Following Cranial Nerves accepts information From the Corlis Organ?

  1. Auditory
  2. Vagus
  3. Oculomotor
  4. Trigeminal.

Answer: 1. Auditory

Question 10. Meissner Corpuscles Are Responsible For :

  1. Heat And Present In Skin
  2. Cold And Present In Skin
  3. Pressure And Present In Skin
  4. Pain And Present In Skin.

Answer: 3. Pressure And Present In Skin

Question 11. The Animals Who Can See Well At Night Have Abundant In Their Eyes.

  1. Cone Cells
  2. Scotopic Pigments
  3. Rod Cells
  4. Vision Cell.

Answer: 3. Rod Cells

Question 12. Excess Or Less Of Air Pressure In the Car Is Balanced By :

  1. Custiichinn Tube
  2. Car Ossicles
  3. Car Muscles
  4. Ear Pinna.

Answer: 1. Custiichinn Tube

PSEB Class 11 Biology Chapter Sense Organs MCQs

Question 13. The Receptors Found In The Muscles, Tendons And Joints Are :

  1. Teloreceptors
  2. Proprioceptors
  3. Intcroccptors
  4. Thermoreceptors.

Answer: 2. Proprioceptors

Question 14. When The Intensity Of Light Is Low During Night The Light Is Detected By :

  1. Rods
  2. Cones
  3. Lens
  4. Both 1 And 2.

Answer: 1. Rods

Question 15. Which Of The Following Is Concerned With Static Equilibrium?

  1. Semicircular Canals And Cochlea
  2. Semicircular Canals And Utricle
  3. Lagena And Sacculus
  4. Otolith And Lagena.

Answer: 2. Semicircular Canals And Utricle

Question 16. Ommatidia Serve The Purpose Of Photoreception In :

  1. Frog
  2. Sunflower
  3. Cockroach
  4. Human.

Answer: 3. Cockroach

PSEB Class 11 Biology Sense Organs MCQs

Question 17. Human Ear Is Equipped To Register Sounds Of Frequencies Per Second Between :

  1. 20-20000 Cycles
  2. 1000-2000 Cycles
  3. 5000-7000 Cycles
  4. 5000-10000 Cycles.

Answer: 1. 20-20000 Cycles

Question 18. Retina Is Similar To Which Part Of Camera?

  1. Lens
  2. Film
  3. Flash
  4. Shutter.

Answer: 2. Film

Question 19. Sensory Cells For Picking Up Sound Vibrations Are Present In :

  1. Utriculus
  2. Cochlea
  3. Sacculus
  4. Semicircular Canal.

Answer: 2. Cochlea

Question 20. Circular Ciliary Muscles Of the Eye Are Unable To Contract. It Will Result In :

  1. Impairment Of Vision
  2. Making Lens More Convex
  3. Making Lens Thin And Stretched
  4. No Effect Of Bright Light On Retina.

Answer: 3. Making Lens Thin And Stretched

Question 21. The Point In the eyeball from Which the Optic Nerve And Blood Vessels Leave Is :

  1. Pass Optica
  2. Pupil
  3. Blind Spot
  4. Yellow Spot.

Answer: 3. Blind Spot

Question 22. In A Man, Abducens Nerve Is Injured. Which One Of The Following Functions Will Be Affected?

  1. Movement Of The Eye Ball
  2. Swallowing
  3. Movement Of The Longue
  4. Movement Of The Neck

Answer: 1. Movement Of The Eye Ball

Question 23. Internal Ear Is Filled With

  1. Perilymph
  2. Endolymph
  3. Lymph
  4. Both 1 And 2

Answer: 2. Endolymph

Question 24. Rods And Cones Of Eye Are Modified:

  1. Multipolar Neuron
  2. Unipolar Neuron
  3. Bipolar Neuron
  4. None Of These.

Answer: 2. Unipolar Neuron

Question 25. Sense Of Smell Is Perceived By :

  1. Pituitary
  2. Hypothalamus
  3. Olfactory Lobe
  4. Cerebrum.

Answer: 3. Olfactory Lobe

Sense Organs Multiple Choice Questions PSEB Class 11

Question 26. Ora Sonata Is :

  1. Gland Present In The Oral Cavity Of Frog
  2. A Part Of The Third Wall Of the Retina Of the Eye
  3. Present In Utriculus Of Ear
  4. Oral Cavity Of Protochordates

Answer: 2. A Part Of the Third Wall Of the Retina Of the Eye

Question 27. Adaptation Of Eyes In Dark Is Due To :

  1. Depletion Of Vision Pigment In Rods
  2. Depletion Of Vision Pigment In Cones
  3. Repletion Of Vision Pigment In Rods
  4. Repletion Of Vision Pigment In Cones.

Answer: 3. Repletion Of Vision Pigment In Rods

Question 28. Feelings Of Anger, Pain And Pleasure Are Experienced Through :

  1. Limbic System
  2. Frontal Lobe
  3. Parietal Lobe
  4. Reticular System.

Answer: 1. Limbic System

Question 29. In Which Of Following Only Cone Cells Are Found?

  1. Fovea Centralis
  2. Retina
  3. Fossa ovalis
  4. Blind Spots.

Answer: 1. Fovea Centralis

Question 30. Bowman’s Glands Are Found In :

  1. External Autjitary Canal
  2. Cortical Nephrons Only
  3. Juxtamedu]Lpy Nephrons
  4. Olfactory Epithelium.

Answer: 4. Olfactory Epithelium.

Question 31. Identity’ The Correct Sequence Of Organs/Regions In The Organization Of Human Ear As An Auditory MechanoReceptor Organ :

  1. Pinna-Cochlea-Tympanic Membrane-Audiory Canal-Malleus-Stapes-Incus-Auditory Nerve
  2. Pinna-Auditory Canal-Tympanic Membrane- Malleus-Incus-Stapes-Cochlea-Auditory Nerve
  3. Pinna-Tympanic Membrane-Auditory Canal-Incus- Malleus-Stapes-Cochlea-Auditory Nerve
  4. Pinna-Tympanic Membrane-Auditory Canal- Cochls-Malleus-Lncus-Stapes-Auditory Nerve.
  5. Pinna-Malleus-Incus-Stapes-Auditory Canal- Tympanic Membrane-Cochlea-Auditory Nerve.

Answer: 2. Pinna-Auditory Canal-Tympanic Membrane- Malleus-Incus-Stapes-Cochlea-Auditory Nerve

Question 32. Muller’s Cells Occur In :

  1. Heart
  2. Retina
  3. Kidney
  4. Pancreas.

Answer: 2. Retina

Sense Organs Multiple Choice Questions PSEB Class 11

Question 33. Jacobson’s Otguns Which Arc Additional Olfactory Organs Ate Present In :

  1. Rat
  2. Man
  3. Snake
  4. All Of These.

Answer: 3. Snake

Question 34. Given Below Is A Diagrammatic Cross Section Of A Single Limp Of Human Cochlea Which One Of The Following Options Correctly Re-Presents The Names Of Three Different Parts?

Sense Organs Given Below Is A Diagrammatic Cross Section Question 34

  1. 4: Sensory Hair Cells, 2: Endolymph 2: Tectorial Membrane 4 Semom Air Cell
  2. 1: Perilymph, 2 Tectorial Membrane 3: Endolymph 4. Secretory Hair Cells
  3. 2: Tectorial Membrane, 3: Parilymph, 4 Secretory Cells
  4. 3: Endolymph, 5: Sensory Hair Cells, 1: Serum.

Answer: 2. 1: Perilymph, 2 Tectorial Membrane 3: Endolymph 4. Secretory Hair Cells

Question 35. Fovea In The Eye Is A Central Pit In The Yellowish Pigmented Spot Called

  1. Blind Spot
  2. Retina
  3. Cornea
  4. Macula Lutea
  5. Choroid.

Answer: 4. Choroid.

Question 36. The Purplish Red Pigment Rhodopsin Contained In The Rods Type Of Photoreceptor Cells Of The Human Eye, Is A Derivative Of :

  1. Vitamin B,
  2. Vitamin C
  3. Vitamin D
  4. Vitamin A

Answer: 4. Vitamin A

PSEB Class 11 Biology Chapter Sense Organs MCQs

Question 37. Parts A, B, C And D Of The Human Eye Are Shown In The Diagram. Select The Option Which Gives Correct Identification Along With Its Functions/Characteristics :

Parts Of The Human Eye Shown In The Diagram Question 37

  1. 2-Blind Spot-Has Only A Few Rods And Cones.
  2. 3-Aqueous Chamber- Reflects The Light Which Does Not Pass Through The Lens.
  3. 4-Choroid- The Anterior Part Forms the Ciliary Body.
  4. 1-Retina – Contains Photoreceptors – Rods And Cones.

Answer: 4. A-Retina – Contains Photoreceptors – Rods And Cones.

PSEB 12th Class Biology Evidence Of Evolution Relationship Among Organisms MCQS

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Evidence Of Evolution Relationship Among Organisms Question and Answers

Question 1. Match the names of the persons listed under Column A with the contributions given in Column B; choose the choice which gives the correct combination of the alphabet:

Evidences Of Evolution Relationship Among Organisms Match The Column Question 1

  1. 1 = r, 2 = t, 3 = p, 4 = q.
  2. 1 = t, 2 = r, 3 = q,4 = p.
  3. 1 = p, 2 = q, 3 = r, 4 = s.
  4. 1 = r, 2 = p, 3 = t, 4 = q.

Answer: 4. 1 = r, 2 = p, 3 = t, 4 = q.

Read and Learn More 12th Class Biology MCQs

Question 2. Which one is not vestigial in humans?

  1. Third molar
  2. Coccyx
  3. Segmental abdominal muscles
  4. Finger nails.

Answer: 4. Fingernails.

Question 3. Coal has been mainly formed by:

  1. Bryophytes
  2. Pteridophytes/pteridosperms
  3. Angiosperms
  4. Algae.

Answer: 2. Pteridophytes/pteridosperms

PSEB 12th Class Biology Evidence of Evolution MCQs

Question 4. Darwin’s finches provide evidence of evolution from:

  1. Anatomy
  2. Morphology
  3. Biogeography
  4. All the above.

Answer: 3. Biogeography

Question 5. The vestigial pelvic girdle and bone remnants of hind limbs are characteristic of:

  1. Whale
  2. Dolphin
  3. Shark
  4. Seal.

Answer: 1. Whale

PSEB 12th Class Biology Evidence Of Evolution Relationship Among Organisms MCQS

Question 6. Monkeys and some lower groups have certain blood groups which are:

  1. Identical to those of man
  2. Identical to those of anthropoid apes
  3. Somewhat similar to white persons
  4. Not identical to those of man.

Answer: 1. Identical to those of man

Question 7. The heart is four-chambered in:

  1. Amphibia
  2. Fishes
  3. Mammals
  4. Reptiles.

Answer: 3. Mammals

Question 8. A living organism with the oldest fossil history is:

  1. Dinosaur
  2. Archaeopteryx
  3. Horse
  4. Man.

Answer: 3. Horse

Question 9. Homologous organs are:

  1. Human eyes and Squid eyes
  2. Gills of Fish and lungs of Man.
  3. Hands of Man and Wings of Bat
  4. Leaf of Moss and a frond of Fern.

Answer: 3. Hands of Man and wings of Bat

Question 10. The occurrence of endemic species in South America and Australia is due to

  1. These species have been extinct in other regions
  2. Continental separation
  3. There is no terrestrial route to these places
  4. Retrogressive evolution.

Answer: 2. Continental separation

Evidence of Evolution Relationship Among Organisms MCQs PSEB Class 12

Question 11. Similarities in organisms with different genotypes indicates:

  1. Microevolution
  2. Macroevolution
  3. Convergent evolution
  4. Divergent evolution

Answer: 2. Macroevolution

Question 12. Convergent evolution is illustrated by:

  1. Dogfish and whale
  2. Rat and dog
  3. Bacterium and protozoan
  4. Starfish and cuttlefish.

Answer: 1. Dogfish and whale

Question 13. Which one of the following is categorized under living fossils?

  1. Metasequoia
  2. Ficus
  3. Cycas
  4. Selaginella.

Answer: 3. Cycas

Question 14. In which branch do we study about remains of plant life?

  1. Palaeontology
  2. Palaeobotany
  3. Eugenics
  4. Palynology.

Answer: 2. Palaeobotany

Question 15. Flippers of the seal are modified:

  1. Hind limbs
  2. Forelimbs
  3. Fins
  4. Gills.

Answer: 2. Forelimbs

Question 16. A baby was born with a small tail. It is a case of exhibiting:

  1. Retrogressive evolution
  2. Atavism
  3. Mutation
  4. Metamorphosis.

Answer: 2. Atavism

Question 17. Which of the following is a living fossil?

  1. Saccharomyces
  2. Spirogyra
  3. Cycas
  4. Moss.

Answer: 3. Cycas

Question 18. The age of fossils in the past was determined by the radioactive carbon method and other methods involving radioactive elements found in the rocks. More precise methods, which were used recently and led to the revision of evolutionary periods from different groups of organisms:

  1. Electron spin resonance and fossil DNA
  2. Study of carbohydrates/proteins in the rocks
  3. Study of carbohydrates/proteins in the fossils
  4. Study of conditions of fossilization.

Answer: 1. Electron spin resonance and fossil DNA

Class 12 Biology Chapter Evidence of Evolution MCQs

Question 19. Potato and sweet potato have edible parts which are:

  1. Analogous
  2. Homologous
  3. Recent introductions
  4. Two species of the same genus.

Answer: 1. Analogous

Question 20. Which of the following is not a vestigial organ in humans?

  1. Ear pinna muscles
  2. Nictitating membrane
  3. Mammary glands in males
  4. Knee bone.

Answer: 4. Knee bone.

Question 21. Trilobites evolved during:

  1. Silurian
  2. Cambrian
  3. Precambrian
  4. Devonian.

Answer: 2. Cambrian

Question 22. Which of the following is not vestigial in humans?

  1. Coccyx
  2. Nail
  3. Third molar
  4. Segmental muscles of the abdomen.

Answer: 2. Nail

Question 23. Which of these pairs is vestigial?

  1. Coccyx and car pinna muscles
  2. Coccyx ana premolar
  3. Facial hair in ladies
  4. Coccyx and intercostal muslces.

Answer: 1. Cococyx and car pinna muscles

Class 12 Biology Chapter Evidence of Evolution MCQs

Question 24. Which of the following points towards common ancestry?

  1. Eye of octopus and of mammal
  2. Vertibsate hearts
  3. Atavism
  4. All of above

Answer: 4. All of the above

Question 25. The eyes of the octopus and the eyes of the cat show different patterns of structure, yet they perform similar functions. This is an example of:

  1. Analogous organs that have evolved due to convergent evolution
  2. Homologous organs that have evolved due to divergent evolution.
  3. Analogous organs that have evolved due to divergent evolution.
  4. Homologous organs that have evolved due to convergent evolution.

Answer: 1. Analogous organs that have evolved due to convergent evolution

Question 26. Which of the following is the relatively most accurate method for dating of fossils?

  1. Uranium-lead method
  2. Potassium-argon method
  3. Electron-spin resonance method
  4. Radiocarbon method.

Answer: 3. Electron-spin resonance method

Question 27. The evolutionary history of an organism is known as:

  1. Palaeontology
  2. Ontogeny
  3. Phylogeny
  4. Ancestry.

Answer: 3. Phylogeny

Question 28. Which one of the following is not a living fossil?

  1. Archaeopteryx
  2. King crab
  3. Peripatus
  4. Sphenodon.

Answer: 1. Archaeopteryx

Question 29. An important evidence in favour of organic evolution is the occurrence of:

  1. Homologous organs only
  2. Homologous and analogous organs
  3. Analogous and vestigial organs
  4. Homologous and vestigial organs.

Answer: 2. Homologous and analogous organs

Question 30. The age of fossils or dating of fossils can be best estimated by:

  1. Radioactive carbon (C14) dating method
  2. Radioactive clock method
  3. Potassium-argon method
  4. None of the above.

Answer: 1. Radioactive carbon (C14) dating method

PSEB 12th Class Biology Evolution MCQs with Answers

Question 31. The example which best explains the atavism is:

  1. Nictitating membrane
  2. Wisdom teeth
  3. Vermiform appendix
  4. Long thick and dense hair.

Answer: 4. Long thick and dense hair.

Question 32. Which of the following gives the correct evidence from the connecting link?

  1. Ornithorhynchus — Between Amphibia and Reptiles
  2. Baltuwglossus — Between Protozoa and Porifera
  3. Neopilinct — Between MolluscaandEchinodcrmata
  4. Peripatus — Between Annelida and Arthropoda.

Answer: 4. Peripatus — Between Annelida and Arthropoda.

Question 33. Jurassic period of the Mesozoic era is characterised by

  1. Dinosaurs become extinct and angiosperms appear
  2. Flowering plants and the first dinosaurs appear
  3. Gymnosperms arc dominant plants and the first birds appear
  4. Radiation of reptiles and origin of mammal-like reptiles.

Answer: 3. Gymnosperms arc dominant plants and the first birds appear

Question 34. Which one of the following statements is correct?

  1. There is no evidence of the existence of gills during embryogenesis of mammals
  2. All plant and animal cells are totipotent
  3. Ontogeny repeats phylogeny
  4. Stem cells are specialized cells.

Answer: 3. Ontogeny repeats phylogeny

Question 35. The Finches of Galapagos islands provide an evidence in favour of:

  1. Evolution due to Mutation
  2. Retrogressive Evolution
  3. Biogeographical Evolution
  4. Special Creation.

Answer: 3. Biogeographical Evolution

Question 36. When two species of different genealogy come to resemble each other as a result of adaptation, the phenomenon is termed:

  1. Microevolution
  2. Co-evolution
  3. Convergent evolution
  4. Divergent evolution

Answer: 3. Convergent evolution

Question 37. Myrmecobius and Myrmecophaga are closely related and have similar adaptations for the same habitat. This phenomenon is

  1. Homoplasy
  2. Parallel evolution
  3. Divergent evolution
  4. Convergent evolution.

Answer: 2. Parallel evolution

PSEB 12th Class Biology Evolution MCQs with Answers

Question 38. Which one of the following options gives one correct example of convergent evolution and divergent evolution?

Convergent And Divergent Evolution

Answer: 4

PSEB Solutions For Class 12 Biology Evolution Multiple Choice Questions

by

Question 1. A rapidly growing population experiences increasing genetic variability because:

  1. There is a greater chance for polymorphism in large populations
  2. The mutation rate is higher for large populations
  3. There is less selective pressure
  4. A large population can support more genetic experimentation
  5. Heterozygote superiority is selectively favoured.

Answer: 4. Heterozygote superiority is selectively favoured.

Question 2. When food is distributed in such a way that an animal must spend a large part of its day wandering from one place to another to find enough to eat, what type of mating system would you expect it to have?

  1. Monogamy
  2. Polyandry
  3. Polygamy
  4. Polygyny.

Answer: 3. Polygamy

Question 3. A human male who remains a bachelor is most likely to enhance his evolutionary success by altruistic behaviour towards the children of:

  1. His sister
  2. His brother
  3. His mother
  4. His grandmother.

Answer: 3. His mother

Read and Learn More 12th Class Biology MCQs

Question 4. In light of the definition of evolution, which of the following is not capable of evolving?

  1. A population of deer
  2. The colour of a population of moths
  3. Your biology teacher
  4. The millions of bacteria in your large intestine.

Answer: 3. Your biology teacher

PSEB Solutions Class 12 Biology Evolution MCQs

PSEB Solutions For Class 12 Biology Evolution Multiple Choice Questions

Question 5. Which of the following did Kettlewell conclude from his studies on industrial melanism in moths?

  1. A dark moth lays more eggs than a light moth in industrial areas
  2. Dark moths are more resistant to pollution than are light moths
  3. Pollution caused some moths to become darker than others
  4. Dark moths are more likely to survive in polluted areas than light moths.

Answer: 4. Dark moths are more likely to survive in polluted areas than light moths.

Question 6. Which bird is most evolutionarily successful

  1. Lays 9 eggs, 8 Hatch and 2 reproduce
  2. Lays 2 eggs, 2 hatches and 2 reproduce
  3. Lays 9 eggs, 9 hatches and 2 reproduce
  4. Lays 7 eggs, 5 hatches and 4 reproduce.

Answer: 4. Lays 7 eggs, 5 hatches and 4 reproduce.

Question 7. Suppose that you have a pack of 50 assorted dogs. You select the largest male and the largest female from the group, mate them, and sterilize the other members of the pack. Assuming that food supplies remain adequate, you should expect that, in the next generation of dogs:

  1. The young dogs will be, on average, larger than their two parents
  2. The young dogs will be, on average, larger than the older members of the pack
  3. The young dogs will be the same average size as the older dogs
  4. All of the young dogs will be larger than the older dogs.

Answer: 2. The young dogs will be, on average, larger than the older members of the pack

Question 8. What is petrification?

  1. Evolution of pteridophytes
  2. Decay of nitrogenous materials by bacteria
  3. A process of fossil formation
  4. Origin of birds from reptiles.

Answer: 3. A process of fossil formation

Question 9. The main dictates of Lamarck’s theory is/are:

  1. All the mentioned below
  2. Effect of environment
  3. Effect of use and disuse of organs.
  4. Inheritance of acquired characters.

Answer: 1. All the mentioned below

Question 10. For evolutionary success, a mutation occurs in:

  1. Germplasm RNA
  2. Somatic DNA
  3. Somatic RNA
  4. Germplasm DNA.

Answer: 4. Germplasm DNA.

PSEB Solutions Class 12 Biology Evolution MCQs

Question 11. The idea of natural selection as the fundamental process of evolutionary change was reached by:

  1. Charles Darwin in 1859
  2. Charles Darwin and A.R. Wallace in 1859
  3. C. Darwin and A.R. Wallace in 1890
  4. A.R. Wallace in 1891.

Answer: 2. Charles Darwin and A.R. Wallace in 1859

Question 12. Industrial melanism is an example of:

  1. Neo-Lamarckism
  2. Natural selection
  3. Neo-Darwinism
  4. Mutation.

Answer: 2. Natural selection

Question 13. The role of mutation in evolution is:

  1. Genetic drift
  2. Genetic variation
  3. Reproductive isolation
  4. None of them.

Answer: 2. Genetic variation

Question 14. One of the following is obtained by artificial selection:

  1. Kohlrabi
  2. Cabbage
  3. Cauliflower
  4. All the above.

Answer: 1. Kohlrabi

Question 15. The frequency of a mutant gene in a population is expected to increase if the gene is:

  1. Sex-linked
  2. Recessive
  3. Favourably selected
  4. Dominant.

Answer: 3. Favourably selected

Question 16. The term isolating mechanism was coined by:

  1. Duritez (1930)
  2. Wagner (1868)
  3. Dobzhansky (1937)
  4. Blain (1941).

Answer: 3. Dobzhansky (1937)

Question 17. Who is known as the father of evolution?

  1. Lamarck
  2. Charles Darwin
  3. Wallace
  4. Erasmus Darwin.

Answer: 2. Charles Darwin

Class 12 Biology Evolution Multiple Choice Questions PSEB

Question 18. The evolution resulting in the formation of new species is known as:

  1. Microevolution
  2. Macroevolution
  3. Both (1) and (2)
  4. Mega evolution.

Answer: 2. Macroevolution

Question 19. Macroevolution operates above species level and results in the establishment of:

  1. New genera
  2. New Families
  3. New orders
  4. All of the above.

Answer: 4. All of the above.

Question 20. In speciation which of the following is most important:

  1. Mutation
  2. Natural selection
  3. Isolation
  4. All the above.

Answer: 4. All the above.

Question 21. Darwin’s finches are:

  1. Water birds
  2. A group of ducks occurring in the Galapagos Islands
  3. Birds of the family Geospizidae
  4. Birds of family Galapagos.

Answer: 3. Birds of the family Geospizidae

Question 22. Which of the following statements is false?

  1. Sympatric species originate by the sudden development of reproductive isolation between segments of a species population due to sudden changes in their genotype
  2. The sum total of genes of all the species in an area constitutes the gene pool.
  3. The gene frequency refers to the proportion of an allele in the gene pool as compared with other alleles
  4. A deme is a community of potentially interbreeding individuals at a given locality which share a single gene pool.

Answer: 2. The sum total of genes of all the species in an area constitutes the gene pool.

Question 23. Parallelism is:

  1. Adaptive convergence of closely related species in evolution
  2. Adaptive divergence in evolution
  3. Adaptive convergence of widely different species in evolution
  4. None of these.

Answer: 1. Adaptive convergence of closely related species in evolution

Question 24. Two accessory processes which contribute towards the occurrence of evolution are:

  1. Migration and Inbreeding
  2. Migration and hybridization
  3. Migration and population mixing
  4. Migration and asexual reproduction.

Answer: 2. Migration and hybridization

Question 25. _________ was the first person who considered the real meaning of fossils:

  1. Aristotle
  2. Anaximander
  3. Francisco Redi
  4. None of the above.

Answer: 2. Anaximander

Question 26. Which of the following is a matching set?

  1. Survival of the fittest – Lamarck
  2. Recapitulation Theory – De Vries
  3. Theory of Pangenesis – Darwin
  4. Use and disuse Theory – Wallace.

Answer: 3. Theory of Pangenesis – Darwin

Question 27. Class Reptilia first appears in the fossils records in:

  1. Pennsylvanian period
  2. Permian period
  3. Cretaceous period
  4. None of the above.

Answer: 1. Pennsylvanian period

Question 28. The initial appearance of reptiles from amphibian ancestors to completely terrestrial habitat is an example of:

  1. Microevolution
  2. Macroevolution
  3. Mega evolutions
  4. Speciation.

Answer: 1. Microevolution

Class 12 Biology Evolution Multiple Choice Questions PSEB

Question 29. The complete evolution of the horse has taken about:

  1. 60 million years
  2. 50 million years
  3. 70 million years
  4. 90 million years.

Answer: 3. 70 million years

Question 30. What is the essence of evolution?

  1. Present-day species are the modified descendants of pre-existing ones
  2. Species are changeable and mutable
  3. Progressive development of simpler organisation into complex forms
  4. All the above.

Answer: 4. All the above.

Question 31. In the course of evolution:

  1. Reptiles have given rise to birds
  2. Amphibians have given rise to reptiles
  3. Ferns have given rise to gymnosperms
  4. All the above.

Answer: 4. All the above.

Question 32. The concealing type of protective mimicry is associated with:

  1. White crabs
  2. Flat fishes
  3. Pupae of Swallowtail butterfly
  4. All of the above.

Answer: 4. All of the above.

Question 33. Phyllopteryx equus (Australian sea horse) shows:

  1. Warning mimicry
  2. Concealing mimicry
  3. Both (1) and (2)
  4. None of the above.

Answer: 2. Concealing mimicry

Question 34. Natural selection that favours heterozygotes is called:

  1. Balancing selection
  2. Heterosis
  3. Progressive selection
  4. Stabilizing selection.

Answer: 1. Balancing selection

Question 35. The type of selection that tends to increase the amount of variance within populations is termed:

  1. Stabilizing selection
  2. Frequency-dependent selection
  3. Directional selection
  4. Disruptive selection.

Answer: 4. Disruptive selection.

Question 36. Condensation of the phylogenetic events and the elimination of others in the embryonic development is referred to as:

  1. Pathogenesis
  2. Coenogenesis
  3. Techygenesis
  4. Ontogenesis.

Answer: 3. Techygenesis

Question 37. The theory of natural selection of Darwin was based on:

  1. Variations, which are inherited, will give rise to new species
  2. Good traits are preserved
  3. The prodigality of reproduction, mass production of species, large number of birth rate and survival of the fittest
  4. Mass conservation of mutations.

Answer: 3. Prodigality of reproduction, mass production of species, large number of birth rate and survival of the fittest

PSEB Class 12 Biology Chapter Evolution

Question 38. Persons who do hard manual work with their hands are likely to develop:

  1. Greater number of sweat pores in their hands
  2. A greater quantity of melanin all over the body
  3. Thick subcutaneous fat in their palms
  4. The thick epidermis on their palms.

Answer: 4. Thick epidermis on their palms.

Question 39. Modem synthetic theory of evolution is based on:

  1. Genetic and chromosomal mutations
  2. Genetic recombination and natural selection
  3. Reproductive isolation
  4. All of these.

Answer: 4. All of these.

Question 40. The present giraffe has a long neck as compared to its ancestors. It could be due to:

  1. Isolation
  2. Speciation
  3. Inheritance of acquired characters
  4. Natural Selection.

Answer: 4. Natural Selection.

Question 41. What is important for a species to survive in a changing environment:

  1. Change in morphology.
  2. Ecological variability
  3. Genetic variability
  4. Reproduction.

Answer: 3. Genetic variability

Question 42. The role of isolation in evolution is:

  1. Differentiation of species
  2. Maintenance of species
  3. Extermination of species
  4. Evolutionary divergence.

Answer: 1. Differentiation of species

Question 43. Being all mammals whales, dolphins, bats, and monkeys show important common characteristics but they also show conspicuous differences. This is due to the phenomenon of:

  1. Normalization
  2. Genetic drift
  3. Convergence
  4. Divergence.

Answer: 4. Divergence.

Question 44. Darwin’s theory gets much recognition because:

  1. It tells about natural selection
  2. It tells about the survival of the fittest
  3. It is a logical sequence of events that should have occurred
  4. It was proposed by an intellectual of his time.

Answer: 3. It is a logical sequence of events that should have occurred

Question 45. Birds and mammals in the geological development of earth arose in the period:

  1. Permian
  2. Carboniferous
  3. Jurassic
  4. Ordovician.

Answer: 3. Jurassic

Question 46. “Evolution can be regarded as the effect of natural selection on the continuous appearance of mutant forms.” What reason would you give to it?

  1. Darwinism
  2. Lamarckism
  3. Neo-Darwinism
  4. De Vries Mutation theory.

Answer: 3. Neo-Darwinism

PSEB Class 12 Biology Chapter Evolution

Question 47. Experimental evidence of the selection of bacteria by using the replica technique was demonstrated by:

  1. Prof. A.D. Bradshaw
  2. Prof. Y.D. Tyagi
  3. J. Lederberg and E. Ledcrberg
  4. Alfred Russel Wallace.

Answer: 3. J. Lederberg and E. Ledcrberg

Question 48. Successful adaptation means:

  1. Moving to a new means
  2. Producing fertile offspring
  3. An increase in fitness
  4. Evolving new characteristics.

Answer: 2. Producing fertile offspring

Question 49. Regarding evolution. Darwin’s explanation is that:

  1. Certain species have ‘built-in’ plans of evolution
  2. Those traits used most often persist longer
  3. Progressive adaptations enable one species to have more offspring
  4. Code determines which species should evolve.

Answer: 3. Progressive adaptations enable one species to have more offspring

Question 50. Which of the following is not inheritable?

  1. Point mutation
  2. Chromosomal mutation
  3. Gene mutation
  4. Somatic mutation.

Answer: 4. Somatic mutation.

Question 51. Organic evolution would not have taken place if:

  1. Individuals in a population did not show genetic variation
  2. The individual did not transmit the characteristics acquired during their lifetime to offspring
  3. Somatic variations did not get inherited
  4. Somatic variations did not get transformed into genetic variation.

Answer: 1. Individual in a population did not show genetic variation

Question 52. Under which of the following conditions organic evolution could not have taken place:

  1. Acquired characters were not inherited
  2. Somatic variations are not inherited
  3. Individuals in a population did not exhibit genetic variation
  4. All of them.

Answer: 3. Individuals in a population did not exhibit genetic variation

Question 53. Lederberg’s replica plating experiment suggests:

  1. Characters are heritable
  2. Natural selection plays an important role in fixing a mutation of survival value
  3. Genes are independent entities
  4. Bacteria can multiply in a culture medium.

Answer: 2. Natural selection plays an important role in fixing a mutation of survival value

Question 54. Which phenomenon of evolution was best explained by Darwin?

  1. Variations occurring in a population
  2. Origin of species by reproductive isolation
  3. Natural selection due to the struggle for existence
  4. All of these.

Answer: 3. Natural selection due to the struggle for existence

Question 55. A good example of mechanical isolation in plants is of:

  1. Oxalis
  2. Calotropis
  3. Salvia
  4. Ficus.

Answer: 2. Calotropis

Question 56. The formation of high milk-yielding cows is an example of the:

  1. Natural selection
  2. Artificial selection
  3. Survival of the fittest
  4. Genetic drift.

Answer: 2. Artificial selection

Question 57. According to Goldschmidt’s classification, evolution of subspecies or geographic races is known as:

  1. Mcgacvolution
  2. Macroevolution
  3. Microevolution
  4. Speciation.

Answer: 3. Microevolution

Question 58. A scientist kept 80 generations of Drosophila in darkness, even after that the flies had normal eyes. This disapproves law of:

  1. Natural selection
  2. Acquired characters
  3. Use and disuse
  4. Synthetic theory.

Answer: 3. Use and disuse

PSEB Class 12 Biology Evolution MCQs with Answers

Question 59. Genetic drift:

  1. Is an orderly change in gene frequencies
  2. Produce the greatest fluctuations in large populations.
  3. Is the random change in gene frequencies
  4. Has nothing in common with inbreeding.

Answer: 1. Is an orderly change in gene frequencies

Question 60. Who considered that gene is the vehicle of inheritance and discontinuous variations could be inherited through genes?

  1. Khorana and Nirenberg
  2. Garrod and Johannsen
  3. Lederberg and Tatum
  4. Bateson and Morgan.

Answer: 4. Bateson and Morgan.

Question 61. Who proposed the concept of intraspecific and interspecific struggle?

  1. De Vries
  2. Malthus
  3. Cuvier
  4. Darwin.

Answer: 4. Darwin

Question 62. Which one of the following is the best example of an evolutionary change in a species of an organism?

  1. Change of colour due to altered environment
  2. Development of thick fur on the hare in winter
  3. Alteration in the DNA structure by radiation
  4. Phenotypic changes in adult Drosophila, when larval development occurs at higher than normal temperatures.

Answer: 3. Alteration in the DNA structure by radiation

Question 63. Darwinism is based on:

  1. Multiplication in a geometrical progression
  2. Existence of variations
  3. Operation of natural selection
  4. All the above.

Answer: 4. All the above.

Question 64. The convergent evolution of two species is usually associated with:

  1. A recent common ancestor
  2. Analogous organ
  3. Homologous organ
  4. Different habitat.

Answer: 2. Analogous organ

PSEB Class 12 Biology Evolution MCQs with Answers

Question 65. A detailed classification of isolating mechanisms was provided by:

  1. Darwin
  2. Dobzhansky
  3. Wagner
  4. Peterson.

Answer: 2. Dobzhansky

Question 66. The isolation caused by differences in the habits of organisms such as food and physiological requirements is called:

  1. Ecological isolation
  2. Ethological isolation
  3. Physiological isolation
  4. None of the above.

Answer: 1. Ecological isolation

Question 67. A post-mating isolating mechanism in which the development of a hybrid zygote is often irregular and may end at any stage between fertilization and adulthood, is known as:

  1. Hybrid inferiority
  2. Hybrid sterility
  3. Hybrid inviability
  4. Gametic mortality.

Answer: 3. Hybrid inviability

Question 68. ______ isolation refers to the barriers to mating among individuals of different species in their courtship behaviour:

  1. Ethological
  2. Mechanical
  3. Ecological
  4. Seasonal.

Answer: 1. Ethological

Question 69. Mutation, natural selection, genetic drift and emigration are considered to be essential factors of evolution. The statement that best explains genetic drift is:

  1. The shifting of a species or population from one place to another
  2. The fixation of adaptive traits in the population
  3. The accidental fluctuations in the frequency of an allele in a population.

Answer: 3. The accidental fluctuations in the frequency of an allele in a population.

Question 70. Neo-Darwinism does not appreciate the role in the evolution of:

  1. Natural selection
  2. Adaptation
  3. Mutations
  4. Germplasm.

Answer: 3. Mutations

Question 71. Which of the following statements is false?

  1. Selection is most effective for recessive mutations
  2. Forces of selection pressure and mutation pressure are antagonistic to each other
  3. Directional selection tends to reduce variance
  4. Natural selection is a creative force in evolution.

Answer: 1. Selection is most effective for recessive mutations

Question 72. The barriers which check the free exchange of genes between populations (subspecies) are called:

  1. Gene barriers
  2. Isolating barriers
  3. Exchange barriers
  4. All the above.

Answer: 2. Isolating barriers

Question 73. Galapagos islands in the Pacific Ocean on the west coast of South America is a chain of:

  1. 41 islands
  2. 14 islands
  3. 4 islands
  4. 141 islands.

Answer: 2. 14 islands

Question 74. In addition to the other books, Darwin also wrote:

  1. Origin of man
  2. Ascent of man
  3. Descent of man
  4. Evolution of man.

Answer: 3. Descent of man

PSEB Class 12 Biology Evolution MCQs with Answers

Question 75. One of the following plants is tolerant to selenium:

  1. Astragalus
  2. Agrostis tenuis
  3. Impatiens balsatuia
  4. Both (1) and (2)

Answer: 4. Both (1) and (2)

Question 76. When a hybrid produces sterile or infertile offspring, it is known as:

  1. Hybrid sterility
  2. Hybrid breakdown
  3. Hybrid inviability
  4. Gametic isolation.

Answer: 3. Hybrid inviability

Question 77. The distribution of land snails in Hawaiian islands affords an example of:

  1. Geographical isolation
  2. Seasonal isolation
  3. Climatic isolation
  4. Habitat isolation.

Answer: 1. Geographical isolation

Question 78. Which of the following is a post-mating isolating mechanism?

  1. Physiological isolation
  2. Hybrid sterility
  3. Mechanical isolation
  4. Ethological isolation.

Answer: 2. Hybrid sterility

Question 79. Point out the pre-mating isolating mechanism from the following:

  1. Gametic mortality
  2. Hybrid inviability
  3. Hybrid inferiority
  4. Isolation due to distance.

Answer: 4. Isolation due to distance.

Question 80. Penguins occur at the south pole while the north pole has polar bears and not penguins. Why?

  1. The south pole is colder than the North Pole
  2. Bears are the evolved form of penguins
  3. These areas are separated geographically from each other
  4. It is a question of special creation.

Answer: 3. These areas are separated geographically from each other

Question 81. Chinese women used to keep their feet enclosed in iron shoes for many years so that their feet remained small in size. Is this character passed on to the next generation?

  1. Yes, as the change is somatogenic
  2. Yes, as the change is blastogenic
  3. No, it is an acquired character
  4. It varies from individual to individual.

Answer: 3. No, it is an acquired character

Question 82. A penguin is a bird that lost the use of its wings by not flying. Such a statement would express the views of:

  1. Darwin
  2. Wallace
  3. Lamarck
  4. Huxley.

Answer: 3. Lamarck

Question 83. An Indian and a Japanese though differing in physical features resemble each other precisely at the level of:

  1. Karyotype
  2. Gene pool
  3. Nutritional requirements
  4. Believing in marriage to get offspring.

Answer: 1. Karyotype

Question 84. The mule is a hybrid of:

  1. Female horse and male ass
  2. Male ass and female zebra
  3. Male ass and male zebra
  4. Female and male zebra

Answer: 1. Female horse and male ass

PSEB Class 12 Biology Evolution MCQs with Answers

Question 85. The hybrid zygotes produced in fishes fail to cleave and develop properly. It is due to:

  1. Hybrid non-viability
  2. Hybrid sterility
  3. Failure to attain sexual maturity
  4. F2 generation sterility.

Answer: 1. Hybrid non-viability

Question 86. Darwinism is based on:

  1. Struggle for existence
  2. Survival of the fittest and natural selection
  3. Origin of new species
  4. All of the above.

Answer: 4. All of the above.

Question 87. Who wrote the essay on Population?

  1. Lamarck
  2. Malthus
  3. Darwin
  4. Morgan.

Answer: 2. Malthus

Question 88. Who proposed the concept of intraspecific and interspecific struggle?

  1. De Vries
  2. Malthus
  3. Darwin
  4. None of the above.

Answer: 3. Darwin

 

PSEB Class 12 Biology Elements Of Heredity And Variations Multiple Choice Questions

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Question 1. Which of die following Mendel’s law has not been proven to be true in all the cases?

  1. Law of segregation
  2. Law of independent assortment
  3. Law of dominance
  4. None of these.

Answer: 3. Law of dominance

Question 2. When the tall red plant is crossed with a dwarf white plant, all the plants of F1 generation are found to be tall red. Which of the following ratios will be available when a test cross is made?

  1. 1: 1 : 1: 1
  2. 1 : 2: 1
  3. 3: 1
  4. 1: 2: 2:1.

Answer: 1.1: 1 : 1: 1

Question 3. The three important laws of heredity proposed by Mendel relate to :

  1. Gene linkage, character segregation and independent assortment
  2. Gene linkage, dominance and segregation
  3. Segregation, independent assortment and dominant recessiveness
  4. Segregation, independent assortment and gene linkage.

Answer: 3. Segregation, independent assortment and dominant recessiveness

Read and Learn More 12th Class Biology MCQs

Question 4. Which one of the following statements is true of Mendel’s theory but not of Darwin’s theory of natural selection?

  1. The original theory was modified later on
  2. The theory immediately and strongly influenced other areas of human knowledge
  3. Clearly defined laws were proposed during the early stages of the theory.
  4. The theory was based mostly on pathological studies.

Answer: 3. Clearly defined laws were proposed during the early stages of the theory.

PSEB Class 12 Biology Elements Of Heredity And Variations MCQs

PSEB Class 12 Biology Elements Of Heredity And Variations Multiple Choice Questions

Question 5. Lethal genes are those which cause :

  1. Die death of the homozygous infant being formed
  2. Night blindness
  3. Colour blindness
  4. Linkage and crossing over.

Answer: 1. Die death of the homozygous infant being formed

Question 6. There is a resemblance between parents and offspring but not the exact likeness. This is because of:

  1. Variations produced by crossing over at the time of gamete formation
  2. Variations produced by chance distribution of chromosomes to the two  poles of meiosis I
  3. Both the above  and  points
  4. None of the above points.

Answer: 3. Both the above  and the points

Question 7. When one gene pair hides the effect of another pair, this phenomenon is referred to as :

  1. Mutation
  2. Epistasis
  3. Dominance
  4. None of the above.

Answer: 2. Epistasis

Question 8. In a dihybrid cross, Fj individuals arc self-crossed, phenotypic ratio  comes to be 15: 1. It is due to :

  1. Duplicate genes
  2. Supplementary genes
  3. Dominant epistasis
  4. Recessive epistasis

Answer: 1. Duplicate genes

Question 9. An Execution of Mendel’s law is:

  1. Independent assortment
  2. Dominance
  3. Purity of gametes
  4. Linkage.

Answer: 4. Linkage.

Question 10. Complementary genes show a ratio of :

  1. 1: 1
  2. 3 :1
  3. 9: 7
  4. 9:3:3: 1.

Answer: 3. 9: 7

Elements Of Heredity And Variations Multiple Choice Questions PSEB Class 12

Question 11. If 3n is the number of genotypes where ‘n’ is the number of different chromosome pairs with each carrying one heterozygous allele, what would be the different genotypes produced by garden pea plant?

  1. 310
  2. 312
  3. 314
  4. 37

Answer: 4. 37

Question 12. If a dihybrid for the character is crossed to a homozygous recessive  individual for the same character, the phenotypic ratio of the progeny  would be :

  1. 1:1:1:1
  2. 1:2:1
  3. 3: 1
  4. 13:3.

Answer: 1. 1:1:1:1

Question 13.Genes which have similar phenotypic effects when present separately but interact to produce a new phenotype when present together are known as :

  1. Supplementary genes
  2. Complementary genes
  3. Epistatic genes
  4. Inhibitory genes.

Answer: 2. Complementary genes

Question 14. In a green pod of pea, the seed-coat colour changed from grey to white. This is an example of:

  1. Chlorosis
  2. Spontaneous mutation
  3. Pleiotropic mutation
  4. Transformation.

Answer: 2. Spontaneous mutation

Question 15. If the genotype of an individual is AA Bb CC, it is a :

  1. Trihybrid
  2. Monohybrid
  3. Dihybrid
  4. None of the above.

Answer: 2. Monohybrid

Question 16. An individual heterozygous for two alleles (Aa Bb) produces two million sperms; how many of the sperms will have both the recessive alleles :

  1. 1 million
  2. 2 million
  3. 0.5 million
  4. 0.25 million.

Answer: 3. 0.5 million

Question 17. If the frequency of a dominant phenotype in a stable population is 75%, the frequency of a dominant allele in the population would be: 

  1. 37.5%
  2. 75%
  3. 9.4%
  4. 50%.

Answer: 4. 50%.

Elements Of Heredity And Variations Multiple Choice Questions PSEB Class 12

Question 18. If two hybrids for the same quantitative character are crossed the phenotypic ratio of progeny would be ;

  1. 1:4 : 6: 4: 1
  2. 15: 1
  3. 12:3:1
  4. 9: 7.

Answer: 1. 1:4 : 6: 4: 1

Question 19.In a cross between a pure tall pea plant with a green pod and a pure short plant with a yellow pod, how many short plants you would expect in F2, generation?

  1. 4
  2. 9
  3. 3
  4. 1.

Answer: 1. 4

Question 20. From a single car of com, a far nu’r planted 200 kernels which produced NO tall and 10 short plants. The genotypes of these offspring are most likely :

  1. TT and Tt only
  2. IT, Tt and tl
  3. tt and tt only
  4. TT and tt only.

Answer: 2. IT, Tt and tl

Question 21. An individual with genotype Aa Bb Co will produce ; 

  1. Four types of gametes
  2. All gametes of the same type
  3. Eight different types of gametes
  4. Four gametes of one type and the remaining gametes Of the same type.

Answer: 3. Eight different types of gametes

Question 22. Mendel was successful in formulating the laws of inheritance whereas his predecessors were not because :

  1. Of the right choice of material
  2. They studied one clear-cut character at a time with no intermediates
  3. The characters studied by him were present on separate chromosomes and  showed no linkage
  4. All the above.

Answer: 4. All the above.

Question 23. A test cross : 

  1. Is commonly used to investigate the genotype of the diploid individual
  2. Involves mating one genotype to another homozygous for all dominant  genes under consideration
  3. Involves mating one genotype to another homozygous for recessive  alleles of all genes under consideration
  4. Both 1 and 3

Answer: 4. Both 1 and 3

Class 12 Biology Chapter Elements Of Heredity And Variations MCQs

Question 24. Mendel formulated the laws of heredity considering seven pairs of characters in the pea plant. If he had studied an eighth pair, the law  which would have been altered is:

  1. Law of segregation
  2. Law of independent assortment
  3. Law of dominance
  4. Law of unit character.

Answer: 2. Law of independent assortment

Question 25. In the F2 generation, genotypic and phenotypic ratios are identical in M case of:

  1. Mendelian nanohybrids
  2. Mendelian dihybrids
  3. Incomplete dominance
  4. None of the above.

Answer: 3. Incomplete dominance

Question 26. The segregation of paired hereditary factors that Mendel postulated occurs during :

  1. Prophase of first meiotic division
  2. Anaphase of first meiotic division
  3. During interphase between two meiotic divisions
  4. Metaphase of the second meiotic division.

Answer: 2. Anaphase of first meiotic division

Question 27. The independent assortment of two pairs of genes located on  non-homologous chromosomes occur as a result of the random orientation of chromosomes during :

  1. Metaphase of the first meiotic division
  2. Telophase of the first meiotic division
  3. The brief interphase between the two meiotic- divisions
  4. Prophase of the second meiotic division.

Answer: 1. Metaphase of the first meiotic division

Question 28. Appearance of hidden character in some progeny of F2 generation proclaims:

  1. Law of Independent assortment
  2. Law of Dominance
  3. Law of Fiuily ol gametes
  4. None of the above,

Answer: 3. Law of Fiuily ol gametes

Question 29. Mendelian recombinations are due to :

  1. Linkage
  2. Modifications
  3. Independent assortment of characters
  4. Mutation.

Answer: 3. Independent assortment of characters

Question 30. Mendel law of segregation is based upon the F2 ratio of:

  1. 1: 2
  2. 1:2:1
  3. 9:3:1
  4. 3: 1

Answer: 4. 3: 1

Class 12 Biology Chapter Elements Of Heredity And Variations MCQs

Question 31. Which one of the following characters in man is controlled by a  recessive gene?

  1. Woolly hair
  2. Brachydactyly
  3. Colour blindness
  4. Night blindness.

Answer: 3. Colour blindness

Question 32. The constriction on chromosomes where the spindle fibres attach during cell division arc :

  1. Chromatids
  2. Chromonemata
  3. Centromere
  4. Chromomere.

Answer: 3. Centromere

Question 32. As a result of linkage and crossing over:

  1. Chromatids become chromosomes
  2. Nuclear divisions come to a close
  3. Chromosomes become half in number
  4. Exchange of chromosomal material occurs.

Answer: 4. Exchange of chromosomal material occurs.

Question 33. Gene P and Q are necessary for normal hearing. A deaf man marries a deaf woman and all their children have normal hearing. The genotypes of the parents are :

  1. PPqq x PPqq
  2. Ppqq x ppQq
  3. PPqq x ppQQ
  4. ppQQ x ppQq.

Answer: 3. PPqq x ppQQ

Question 34.A plant with Aa Bb composition, on self-pollination results in which of the following genetic frequencies among the dominant phenotypes?

AABB : AABb : Aa BB : AaBb

  1. 1 : 2 : 2 : 4
  2. 1 : 2 : 2 : 1
  3. 1 : 1 : 1 : 1
  4. 2:2 :2:3.

Answer: 1. 1 : 2 : 2 : 4

Question 35. “Like begets like” is an important and universal phenomenon of life, is due to :

  1. Euthenics
  2. Inheritance
  3. Dominance
  4. Eugenics.

Answer: 1. Euthenics

Question 36. The father of genetics G.J. Mendel is famous for propounding :

  1. Theory of acquired character
  2. Cell theory
  3. Laws of inheritance
  4. Origin of species.

Answer: 3. Laws of inheritance

PSEB Class 12 Biology Genetics MCQs with Answers

Question 37. The frequency of a mutant gene in a population is expected to increase if the gene is:

  1. Dominant
  2. Recessive
  3. Favourably selected
  4. Sex-linked.

Answer: 1. Dominant

Question 38. Genetic information is carried out by a long chain of molecules made up of:

  1. Enzymes
  2. Nucleotides
  3. Amino acids
  4. Chromosomes.

Answer: 2. Nucleotides

Question 39. Mendel studied seven contrasting characters for his breeding experiments: which of the following characters he did not study?

  1. Plant height
  2. Pod colour
  3. Pod shape
  4. Leaf shape.

Answer: 4. Leaf shape.

Question 40. A normal plant suddenly started producing Parthenon genetically. the number of chromosomes of the second generation compared to the parent plant will be :

  1. Double
  2. One half
  3. One fourth
  4. Same.

Answer: 2. One half

Question 41. Why were pea plants more suitable than dogs for Mendel’s experiments?

  1. There were no pedigree records of dogs
  2. Pea plants can be self-pollinated
  3. Dogs have many genetic traits
  4. All pea plants are diploid.

Answer: 2. Pea plants can be self-pollinated

Question 42. Suppose pea plant’s tallness is dominant over dwarfness, to determine whether a tall pea plant is homozygous or heterozygous, it should be crossed with the:

  1. A homozygous tall pea plant
  2. A homozygous dwarf pea plant
  3. Any tall pea plant
  4. Any pea plant.

Answer: 2. A homozygous dwarf pea plant

Question 43. The term gene was given by :

  1. Bateson
  2. Johannsen
  3. Punnet
  4. Darlington.

Answer: 2. Johannsen

PSEB Class 12 Biology Genetics MCQs with Answers

Question 44. The term back cross refers to :

  1. A cross between F| hybrid and either of the parents
  2. A cross between one Fj-and another Fj hybrid
  3. A cross between Fj hybrid and Fj individuals
  4. None of these.

Answer: 1. A cross between F| hybrid and either of the parents

Question 45. A cross between unlike organisms is called as :

  1. Hybridisation
  2. Heterosis
  3. Backcross
  4. Test cross.

Answer: 1. Hybridisation

Question 46. If Mendel had, by chance, chosen to study two traits determined by linked genes, he would have not been able to derive the :

  1. Law of dominance
  2. Law of independent assortment
  3. Law of unit character
  4. Law of segregation.

Answer: 2. Law of independent assortment

Question 47. The character which predominates and is seen in F, generation is said to be :

  1. Common
  2. Dominant
  3. Special
  4. Recessive.

Answer: 2. Dominant

Question 48. The ratio of recessive epistasis :

  1. 9:3:4
  2. 13:3
  3. 12:3: I
  4. 15: 1.

Answer: 2.13:3

PSEB Class 12 Biology Genetics MCQs with Answers

Question 49. A pure tall pea plant was reared in soil poor in nutrition and reached the size of the pure dwarf pea plant. If this pea plant is selfed  then the phenotype in the F| generation is most likely to be :

  1. All tall
  2. 50% tall and 50% dwarf
  3. All dwarf
  4. Data are insufficient.

Answer: 1. All tall

Question 50. In a monohybrid cross, 2 heterozygous individuals were crossed,  phenotype ratio comes to be 2: 1. It is due to :

  1. Dominant lethal genes in homozygous condition
  2. Dominant lethal genes in heterozygous individuals
  3. Dominant epistasis
  4. None of the above.

Answer: 1. Dominant lethal genes in homozygous condition

PSEB 12th Class Enzymes Multiple Choice Questions

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Enzymes Multiple Choice Questions

Question 1. The enzyme which joins with the non-proteinic part to form a functional enzyme is:

  1. Holoenzyme
  2. Prosthetic group
  3. Apoenzyme
  4. Coenzyme.

Answer: 3. Apoenzyme

Question 2. Enzymes that help in electron transfer are :

  1. Cytochrome
  2. Isomerase
  3. Proteinase
  4. All of the above.

Answer: 1. Cytochrome

Question 3. Induced-fit theory of enzyme action was given by:

  1. Koshland
  2. Sumner
  3. Fischer
  4. Hershey and Chase.

Answer: 1. Koshland

Read and Learn More 12th Class Biology MCQs

Question 4. The most abundant enzyme among living organisms is:

  1. Catalase
  2. Rubisco
  3. Nitrogenase
  4. Invertase.

Answer: 2. Rubisco

PSEB 12th Class Biology Enzymes MCQs

PSEB 12th Class Enzymes Multiple Choice Questions

Question 5. Enzymes speed up the rate of reaction by :

  1. Combining with product
  2. Forming reactant-product complex
  3. Changing the equilibrium of the reaction
  4. Lowering activation energy.

Answer: 4. Lowering activation energy.

Question 6. The enzyme which fixes CO2 in C4 plants, is :

  1. Hydrogenase
  2. Pepcarboxyease
  3. Reductase
  4. Rubp carboxylase.

Answer: 2. Pepcarboxyease

Question 7. Endoenzymes generally act at:

  1. Neutral ph
  2. Alkaline ph
  3. Any ph
  4. Acidic ph.

Answer: 1. Neutral ph

Question 8. The nomenclature of the enzyme consists of :

  1. First name of the product and then reaction name
  2. Only product name
  3. Only reaction name
  4. First reaction, then product name.

Answer: 1. First name of the product and then reaction name

Question 9. Holoenzyme is :

  1. Protein moiety of enzyme
  2. Non-protein moiety of enzyme
  3. Complete enzyme
  4. Inactive enzyme.

Answer: 3. Complete enzyme

Enzymes Multiple Choice Questions PSEB Class 12

Question 10. The energy released from enzyme-substrate interaction is known as:

  1. Activation energy
  2. Binding energy
  3. Constant energy
  4. Variable energy.

Answer: 2. Binding energy

Question 11. The enzyme involved in the hydrolysis of starch to maltose is called:

  1. Sucrase
  2. Amylase
  3. Lactase
  4. Maltase.

Answer: 2. Amylase

Question 12. The hydrolytic enzymes acting at low pH are termed:

  1. Alpha amylase
  2. Hydrolases
  3. Proteases
  4. Pyrimnidases

Answer: 1. Alpha-amylase

Question 13. The glycogen in a dead or killed animal is disintegrated by the enzymatic action to:

  1. Glucose
  2. Fructose
  3. Lactose
  4. None of the above.

Answer: 4. None of the above.

Question 15. Enzymes, vitamins, and hormones can be classified into a single category of biological chemicals because all of these:

  1. Enhance oxidative metabolism
  2. Ale conjugated proteins
  3. Are exclusively synthesized in the body of a living
    an organism as at present.
  4. Help in regulating metabolism

Answer: 4. Help in regulating metabolism

Question 16. Which of the following statements regarding enzyme inhibition is correct?

  1. Non-competitive inhibition of an enzyme can be overcome by adding a large amount of substrate.
  2. Competitive inhibition is seen when a substrate competes with an enzyme for binding to an inhibitor protein.
  3. Competitive inhibition is seen when the substrate and the inhibitor compete for the active site on the
  4. Non-competitive inhibitors often bind to the enzyme irreversibly.

Answer: 3. Competitive inhibition is seen when the substrate and the inhibitor compete for the active site on the

Class 12 Biology Chapter Enzymes MCQs

Question 17. The catalytic efficiency of two different enzymes can be compared by the :

  1. The km value
  2. The pH optimum value
  3. Formation of the product
  4. The molecular size of the enzyme.

Answer: 1. The km value

Question 18. Telomerase is an enzyme that is a :

  1. Repetitive dna
  2. Rna
  3. Simple protein
  4. Ribonucleic protein

Answer: 4. Ribonucleoprotein

Question 19. The figure given below shows three velocity-substrate concentration curves for an enzyme reaction. What do the curves a, b, and c depict respectively?

Image-

  1. A-normal enzyme reaction, b-competitive c-non-competitive inhibition
  2. A-enzyme with an allosteric modulator added, b-normal enzyme activity, c-competitive inhibition
  3. A-enzyme with an allosteric stimulator, b-competitive inhibition added c-normal enzyme reaction
  4. A-normal enzyme reaction. B-non-competitive inhibitor added
    c-allosteric inhibitor added.

Answer: 1. A-normal enzyme reaction, b-competitive c-non-competitive inhibition.

Question 21. In which one of the following sets of three items each belong to the category tensioned against them?

  1. Lysine, glycine, thiamine…..amino acids
  2. Myosin, oxytocin, and gastrin……hormones
  3. Rennin, helicase, and hyaluronidase….enzymes
  4. Optic nerve, oculomotor, vagus…..sensory nerves.

Answer: 3. Rennin, helicase, and hyaluronidase….enzymes

Question 21. Assertion: a coenzyme or metal ion that is very tightly bound to an enzyme protein is called a prosthetic.

Reasons: a complete, catalytically active enzyme together with its bound prosthetic group is called an apoenzyme.

  1. Both and (r) are true and (r) is the correct explanation of the
  2. Both and (r) are true but the (r) is not the correct explanation of the
  3. Is a true statement but (r) is false
  4. Both and (r) are false.

Answer: 3. Is a true statement but (r) is false

Question 22. If by radiation all nitrogenase enzymes are inactivated, then there will be no :

  1. Fixation of nitrogen in legumes
  2. Fixation of atmospheric nitrogen
  3. Conversion from nitrate to nitrite in legumes
  4. Conversion from ammonium to nitrate in soil.

Answer: 1. A fixation of nitrogen in legumes

Question 23. Which of the following cell organelles is rich in catabolic enzymes?

  1. Ribosomes
  2. Chloroplast
  3. Mitochondria
  4. Golgi complex.

Answer: 3. Mitochondria

Question 24. Cytochrome oxidase is a.an :

  1. Coenzyme
  2. Proenzyme
  3. Exoenzyme
  4. Endoenzyme

Answer: 4. Endoenzyme

Question 25. Enzymes found attached to the inner membrane of mitochondria instead of the matrix are :

  1. Succinic acid dehydrogenase
  2. Cytochrome oxidase
  3. Malic acid dehydrogenase
  4. Both 1 and 2.

Answer: 4. Both 1 and 2.

PSEB 12th Class Biology Enzymes Questions with Answers

Question 26. A competitive inhibitor of succinic dehydrogenase is :

  1. Malate
  2. Maionate
  3. Oxaloacetate
  4. A-ketoglutarate

Answer: 2. Maionate

Question 27. An example of feedback inhibition is :

  1. Cyanide action on cytochrome
  2. Sulpha drug on folic acid synthesizer bacteria
  3. Allosteric inhibition of hexokinase by glucose 6- phosphate
  4. Reaction between succinic dehydrogenase and succinate.
  5. The inhibition of succinic dehydrogenase by malonate.

Answer: 3. Allosteric inhibition of hexokinase by glucose 6- phosphate

Question 28. The essential chemical components of many coenzymes

  1. Nucleic acids
  2. Carbohydrates
  3. Vitamins
  4. Proteins

Answer: 3. Vitamins

Question 29. The transition state structure of the substrate formed during an enzymatic reaction is :

  1. Permanent but unstable
  2. Transient an unstable
  3. Permanent and stable
  4. Transient but stable

Answer: 2. Transient an unstable

PSEB 12th Class Biology Evolution Of Man Multiple Choice Questions

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Question 1. What evidence suggests that chimpanzees are more closely related to humans than other hominid species?

  1. DNA from sex chromosomes only
  2. Chromosome morphology only
  3. Fossil remains
  4. DNA of both autosomes and sex chromosomes.

Answer: 4. DNA of both autosomes and sex chromosomes.

Question 2. The cranial cavity of Australopithecus was:

  1. 650-700 cm³
  2. 350-450 cm³
  3. 1050-1150 cm³
  4. 1400-1450 cm³

Answer: 2. 350-450 cm³

Question 3. Tuang baby is:

  1. Dryopithecus
  2. Australopithecus
  3. Peking man
  4. Piltdown man.

Answer: 2. Australopithecus

Read and Learn More 12th Class Biology MCQs

Question 4. Which one of the following apes is found in India:

  1. Gorilla
  2. Gibbon
  3. Chimpanzee
  4. Orangutan.

Answer: 1. Gorilla

PSEB 12th Class Biology Evolution Of Man MCQs

Question 5. Most primary hominids that appeared were:

  1. Pleistocene
  2. Early Miocene
  3. Late Miocene and early Pliocene
  4. Late Pliocene.

Answer: 3. Late Miocene and early Pliocene

PSEB 12th Class Biology Evolution Of Man Multiple Choice Questions

Question 6. There are two opposing views about the origin of modern man. According to one view Homo erectus in Asia were the ancestors of modem man. A study of variations of DNA however suggested the African origin of modern man. What kind of observation of DNA variation could suggest this?

  1. Greater variation in Africa than in Asia
  2. Variation only in Asia and no variation in Africa
  3. Greater variation in Asia than in Africa
  4. Similar variations in Africa and Asia.

Answer: 1. Greater variation in Africa than in Asia

Question 7. The last common ancestor between the African apes and hominids lived during the epoch:

  1. Oligocene
  2. Pliocene
  3. Millocene
  4. Pleistocene.

Answer: 2. Pliocene

Question 8. What was the most significant trend in the evolution of modem (Homo sapiens) from his ancestors?

  1. Binocular vision
  2. Increasing cranial capacity
  3. Upright posture
  4. Shortening of jaws.

Answer: 2. Increasing cranial capacity

Question 9. The cranial capacity of Neanderthal man was about:

  1. 1450 cc
  2. 900 cc
  3. 650 cc
  4. 1100 cc.

Answer: 1. 1450 cc

Question 10. What is the correct sequence of human evolution:

  1. Ramapithecus → Australopithecus → Homo erectus → Neanderthal → Homo sapiens sapiens
  2. Ramapithecus → Homo habilis → Homo sapiens sapiens → Homo erectus
  3. Australopithecus → Ramapithecus → Homo habilis → Homo sapiens sapiens
  4. Homo habilis → Australopithecus → Homo erectus → Homo sapiens sapiens.

Answer: 1. Ramapithecus → Australopithecus → Homo erectus → Neanderthal → Homo sapiens sapiens

Question 11. Among the human ancestors the brain size was more than 1000 cc in:

  1. Homo erectus
  2. Ramapithecus
  3. Homo habilis
  4. Homo neanderthalensis.

Answer: 4. Homo neanderthalensis.

Evolution Of Man Multiple Choice Questions PSEB Class 12

Question 12. What was the most significant trend in the evolution of modem man (Homo sapiens) from his ancestors?

  1. Upright posture
  2. Shortening of jaws
  3. Binocular vision
  4. Increasing brain capacity.

Answer: 4. Increasing brain capacity.

Question 13. Which of the following is used as an atmospheric pollution indicator?

  1. Lepidoptera
  2. Lichens
  3. Lycopersicon
  4. Lycopodium.

Answer: 2. Lichens

Question 14. The theory of spontaneous generation states that:

  1. Life arose from living forms only
  2. Life can arise from both living and non-living
  3. Life can arise from non-living things only
  4. Life arises spontaneously, neither from living nor from the non-living.

Answer: 3. Life can arise from non-living things only

Question 15. Animal husbandry and plant breeding programs are examples of:

  1. Reverse evolution
  2. Artificial selection
  3. Mutation
  4. Natural selection.

Answer: 2. Artificial selection

Question 16. Palaeontological evidence for evolution refers to the.

  1. Development of embryo
  2. Homologous organs
  3. Fossils
  4. Analogous organs.

Answer: 3. Fossils

Question 17. The bones of forelimbs of whales, bats, cheetahs, and man are similar in structure, because:

  1. One organism has given rise to another
  2. They share a common ancestor
  3. They perform the same function
  4. They have biochemical similarities.

Answer: 2. They share a common ancestor

Evolution Of Man Multiple Choice Questions PSEB Class 12

Question 18. Analogous organs arise due to:

  1. Divergent evolution
  2. Artificial selection
  3. Genetic drift
  4. Convergent evolution.

Answer: 4. Convergent evolution.

Question 19. (p+q)² = p² + 2pq + q² = 1 represents an equation used in:

  1. Population genetics
  2. Mendelian genetics
  3. Biometrics
  4. Molecular genetics.

Answer: 3. Biometrics

Question 20. Appearance of antibiotic-resistant bacteria is an example of:

  1. Adaptive radiation
  2. Transduction
  3. Pre-existing variation in the population
  4. Divergent evolution.

Answer: 3. Pre-existing variation in the population

Question 21. Evolution of life shows that life forms had a trend of moving from:

  1. Land to water
  2. Dryland to wetland
  3. Fresh water to seawater
  4. Water to land.

Answer: 4. Water to land

Question 22. Viviparity is considered to be more evolved because

  1. The young ones are left on their own
  2. The young ones are protected by a thick shell
  3. The young ones are protected inside the mother’s body and are looked after they are bom leading to more chances of survival
  4. The embryo takes a long time to develop.

Answer: 3. The young ones are protected inside the mother’s body and are looked after they are bom leading to more chances of survival

Question 23. Fossils are generally found in:

  1. Sedimentary rocks
  2. Igneous rocks
  3. Metamorphic rocks
  4. Any type of rock.

Answer: 1. Sedimentary rocks

Question 24. For the MN-blood group system, the frequencies of M and N alleles arc 0.7 and 0.3, respectively. The expected frequency of MN-blood group-bearing organisms is likely to be.

  1. 42%
  2. 49%
  3. 9%
  4. 58%.

Answer: 1. 42%

Question 25. Which type of selection is industrial melanism observed in moths? Bistort Bulgaria:

  1. Stabilizing
  2. Directional
  3. Disruptive
  4. Artificial.

Answer: 2. Directional

Question 26. The most accepted line of descent in human evolution is:

  1. Australopithecus → Ramapithecus → Home sapiens → homo habilis
  2. Home ercctus → Homo habilis → Homo sapiens
  3. Ramapithecus → Homo habilis → Homo erectus → Homo sapiens
  4. Australopithecus → Ramapithecus → Homo erectus → Homo habilis → Homo sapiens.

Answer: 3. Ramapithecus → Homo habilis → Homo erectus → Homo sapiens

Question 27. Which of the following is an example of connecting link species?

  1. Lobe fish
  2. Dodo bird
  3. Seaweed
  4. Tyrannosaurus rex.

Answer: 1. Lobe fish

Question 28. Match the scientists listed under column ‘A’ with ideas listed in column ‘B’.

  1. 1-A; 2-D; 3-B; 4-C
  2. 1-D; 2-A; 3-B; 4-C
  3. 1-B; 2-D; 3-C; 4-A
  4. 1-D; 2-C; 3-B; 4-A.

Answer: 2. 1-D; 2-A; 3-B; 4-C

Question 29. In 1953 S.L. Miller created primitive earth conditions in the laboratory and gave experimental evidence for the origin of the first form of life from pre-existing non-living organic molecules. The primitive earth conditions created include:

  1. Low temperature, volcanic storms, an atmosphere rich in oxygen
  2. Low temperature, volcanic storms, reduced atmosphere
  3. High temperature, volcanic storms, non-reducing atmosphere
  4. High temperature, volcanic storms, reducing atmosphere containing CH4, NH3, etc.

Answer: 4. High temperature, volcanic storms, reducing atmosphere containing CH4, NH3, etc.

Class 12 Biology Chapter Evolution Of Man MCQs

Question 30. Variations during mutations of meiotic recombinations are:

  1. Random and directionless
  2. Random and directional
  3. Random and small
  4. Random small and directional.

Answer: 1. Random and directionless

Question 31. The essence of Darwinian theory about evolution is:

  1. The rate of appearance of new forms linked to the life cycle
  2. Natural selection
  3. Artificial selection
  4. Both (1) and (2).

Answer: 4. Both (1) and (2).

Question 32. Darwin’s theory of natural selection was influenced by the work of:

  1. Herbert Spencer
  2. Thomas Malthus
  3. Lamarck
  4. I. A. Oparin.

Answer: 2. Thomas Malthus

Question 33. Natural selection is based on certain observations which are factual. They are:

  1. Limited natural resources
  2. Populations are stable
  3. Members of the population vary in characteristics that are inherited.
  4. All the above.

Answer: 4. All the above.

Question 34. Key concepts of Darwinian theory are:

  1. Branching descent
  2. Natural selection
  3. Inheritance of all traits
  4. Both (1) and (2).

Answer: 4. Both (1) and (2).

Question 35. The process of evolution of different species in a given geographical area starting from a point and spreading to other areas is called:

  1. Adaptive radiation
  2. Convergent evolution
  3. Parallel evolution
  4. Co-evolution.

Answer: 1. Adaptive radiation

Question 36. Huge clusters of galaxies comprise the universe. This universe is how many years old?

  1. 200 million
  2. 20 million
  3. 300 billion
  4. 20 billion.

Answer: 4. 20 billion.

Question 37. Big Bang theory explains the origin of the universe. Did life appear on earth about how many years ago?

  1. 500 million after the formation of the earth
  2. 4 billion years ago
  3. 4.5 billion years ago
  4. Both (1) and (2) correct

Answer: 4. Both (1) and (2) correct

Class 12 Biology Chapter Evolution Of Man MCQs

Question 38. Analogous structures are a result of:

  1. Convergent evolution
  2. Divergent evolution
  3. Microevolution
  4. Coevolution.

Answer: 1. Convergent evolution

Question 39. Hardy-Weinberg equilibrium is affected by

  1. Gene flow and genetic drift
  2. Mutation and genetic recombination
  3. Natural selection
  4. All the above.

Answer: 4. All the above.

Question 40. Dinosaurs became extinct during which period:

  1. Jurassic
  2. Cretaceous
  3. Tertiary
  4. Triassic.

Answer: 3. Tertiary

Question 41. The Neanderthal man with a brain size of 1400 cc lived near East and Central Asia between:

  1. 100,000 – 40,000 years ago
  2. 75,000 – 10,000 years ago
  3. 18,000 years ago
  4. 10,000 years ago.

Answer: 1. 100,000 – 40,000 years ago

Question 42. The biggest dinosaurs about 20 ft in height were:

  1. Ichthyosaurs
  2. Tyratmosams
  3. Stegosaur
  4. Triceratops.

Answer: 2. Tyratmosams

Question 43. Which of the following is correct?

  1. Jean-Baptiste Lamarck (1744-1829) a French biologist was an advocate of evolution during the pre-Darwin era.
  2. Lamarck could recognize several lines of descent or lineage of modern species
  3. Lamarck could arrange the fossils in chronological series of order from older to younger form
  4. All are correct.

Answer: 4. All are correct.

Question 44. A new mutation spreads from one population to another by means of:

  1. Removed bottlenecks
  2. Emigrants and immigrants
  3. Mutation pressure
  4. Cross overs.

Answer: 3. Mutation pressure

Question 45. Genetic drift occurs when a few individuals of a species colonize in land. The particular phenomenon is:

  1. Bottleneck effect
  2. The founder effect
  3. Associative mating
  4. Random mating.

Answer: 2. The founder effect

Question 46. A plant population that reproduces by self-pollination is an extreme example of:

  1. The bottleneck effect
  2. The founder effect
  3. Rapid gene flow
  4. Assortative mating.

Answer: 4. Assortative mating.

Question 47. Lumpers tend to:

  1. Separate the same population into different species or group
  2. Combine population into single species or group
  3. Recognize the basic species
  4. All the above.

Answer: 2. Combine the population into single species or group

PSEB 12th Class Biology Human Evolution MCQs with Answers

Question 48. Reproductive isolation in sympatric speciation develops without a:

  1. Geographical barrier
  2. Barrier to mating
  3. Change in chromosome number
  4. The barrier to gene flow.

Answer: 1. Geographical barrier

Question 49. Which of the following is the most rapid method of speciation?

  1. Polyploidy
  2. Sympatric
  3. Allopatric
  4. Isolation.

Answer: 1. Polyploidy

Question 50. Common bread wheat is thought to have arisen through:

  1. Parapatric speciation
  2. Allopatric speciation
  3. Polyploidy and cross-fertilisation
  4. Ecological separation.

Answer: 4. Ecological separation.

Question 51. Which of the following originated during the Miocene epoch in Africa and Asia?

  1. Ramapithcus
  2. Dryopithecus
  3. Sivapithcus
  4. Parapithecus.

Answer: 2. Dryopithecus

Question 52. Homo habilis, a tool maker having a cranial capacity of? 735 cc and bipedal gait existed during which epoch?

  1. Pleistocene
  2. Miocene
  3. Pliocene
  4. Oligocene.

Answer: 1. Pleitostocene

Question 53. The most recent products of animal evolution are:

  1. Birds
  2. Mammal
  3. Snakes and crocodiles
  4. Lizards and turtles.

Answer: 2. Mammal

Question 54. Apes have:

  1. Arms shorter than legs
  2. Arms longer than legs
  3. 900-1500 Cc cranial capacity
  4. Strictly herbivorous feeding habit.

Answer: 2. Arms longer than legs

PSEB 12th Class Biology Human Evolution MCQs with Answers

Question 55. Cromagnon man had:

  1. Highest cranial capacity
  2. Lived in caves and was a hunter
  3. The ability to make tools and weapons
  4. All the above.

Answer: 4. All the above.

Question 56. Which fossil man had a cranial capacity almost equal to modern man?

  1. Peking man
  2. Java ape man
  3. Neanderthal man
  4. Sivapithecus.

Answer: 3. Neanderthal man

Question 57. A cranial capacity of about 1200 cc belongs to

  1. Java man
  2. Peking man
  3. Cromagnon man
  4. Both (1) and (2).

Answer: 2. Peking man

Question 58. Who discovered Java man?

  1. Leaky
  2. Levis
  3. Dubois
  4. Oparin.

Answer: 3. Dubois

Question 59. Handyman is:

  1. Cromagnon man
  2. Neanderthal man
  3. Homo habilis
  4. None of the above.

Answer: 3. Homo habilis

Question 60. The evolution of man came after Dry epithets

  1. Ramapithecus
  2. Proconsul
  3. Shivapilhecus
  4. Australopithecus.

Answer: 1. Ramapithecus

Question 61. Which of the following is closest to man?

  1. Neanderthal
  2. Cromagnon
  3. Homo credits
  4. Homo habilis.

Answer: 2. Cromagnon

Question 62. Which of the following is not a feature of apes?

  1. Absence of tail
  2. Arboreal habitat
  3. Narrow pelvis
  4. Occipital condyles lateral in position.

Answer: 4. Occipital condyles lateral in position.

PSEB 12th Class Biology Human Evolution MCQs with Answers

Question 63. Which of the following is not a feature of present-day man?

  1. More hair
  2. Distinct chin
  3. Bipedal gait
  4. Steep and high brow.

Answer: 1. More hair

Question 64. Which of the following is not a feature of Australopithecus?

  1. Simian gap present
  2. The forward position of the foramen magnum
  3. Basin-like pelvic girdle
  4. Erect posture with four feet height.

Answer: 1. Simian gap present

Question 65. Homo areas show:

  1. Upright bipedal locomotion
  2. 700-800 cranial capacity
  3. Forehead present
  4. Rounded skull.

Answer: 1. Upright bipedal locomotion

Question 66. Six races i.e. Negroid, Casusacoid. Mongaloid, Australcoid, Polynesian, and Bushman were recognized by

  1. May (1950)
  2. Leaky
  3. Mansell (1962)
  4. Colbert (1995).

Answer: 3. Manell (1962)

Question 67. Parapithecus was discovered by:

  1. Gregory
  2. Colbert
  3. Lewis and Leaky
  4. Dubois.

Answer: 2. Colbert

Question 68. Australopithecus African (African ape man) was discovered by

  1. Leaky
  2. Dubois
  3. Raymon Dart
  4. Lewis and Leaky.

Answer: 3. Raymon Dart

Question 69. Gregor discovered Homo sapiens fossils during the late Pleistocene period showed the following characters except:

  1. Broad pelvic basin
  2. Toolmaker
  3. Face orthognathic
  4. Cranial capacity 1200-1500 cm³.

Answer: 4. Cranial capacity 1200-1500 cm³

Question 70. Hominids include:

  1. Homo sapiens
  2. Chimpanzee ana gorilla
  3. Orangutan and gibbons
  4. Lemurs

Answer: 1. Homo sapiens

PSEB Class 11 Biology On Central Nervous System Multiple Choice Questions

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PSEB Class 11 Biology On Central Nervous System Multiple Choice Questions

Question 1. During the Development Of Action Potential In A Nerve Fibre, Positive And Nfor Exampleative Charges On the Outer And Inner sides of the Axon Membrane Are Reversed Due To :

  1. Exteusion Of All K+ Ions
  2. More K+ Ions Enter Than Na+ Ions Leave The Axon
  3. More Na+ Ions Enter The Axon Than K+ Ions Leave The Same
  4. All Na+ Ions Enter The Axon.

Answer: 3. More Na+ Ions Enter The Axon Than K+ Ions Leave The Same

Question 2. Broca Area And Wernicke Centre Of Association Area Occur In Cerebrum. They Are Connected With :

  1. Memory
  2. Voluntary Action
  3. Blind Spot
  4. Both 1 And 2.

Answer: 4. Blind Spot

Question 3. Centre Of Thirst And Hunger Is Located In :

  1. Cerebrum
  2. Cerebellum
  3. Hypothalamus
  4. Medulla Oblongata.

Answer: 3. Hypothalamus

Read And Learn More Class 11 Biology MCQs

Question 4. Common Feature Amongst Acetylcholine, Noradrenaline And Serotonin Is :

  1. All Are Anticoagulants
  2. They Lower Blood Pressure
  3. They Raise Heart Beat
  4. All Are Neurotransmitters.

Answer: 4. All Are Neurotransmitters.

PSEB Class 11 Biology On Central Nervous System Multiple Choice Questions

Question 5. At the Resting Stage Nerve Cell Have:

  1. Low K+ Outside And High Na+ Inside
  2. High K+ Inside And High Na+ Outside
  3. High K+ Inside And Low Na+ Outside.
  4. High K+ Outside And Low Na+ Inside

Answer: 2. High K+ Inside And High Na+ Outside

Question 6. Nerve Axon Takes Part In :

  1. Receiving Impulse
  2. Transformation Of Energy
  3. Conducting Of Impulse
  4. Providing Energy For Impulse Transmission.

Answer: 3. Conducting Of Impulse

Question 7. Venom Of Cobra Affects:

  1. Respiratory System
  2. Nervous System
  3. Circulatory System
  4. Digestive System.

Answer: 2. Nervous System

Question 8. Refractory Period Is During :

  1. Depolarization
  2. Repolarization
  3. Polarization
  4. Both 1 And 2.

Answer: 4. Both 1 And 2.

PSEB Class 11 Biology Central Nervous System MCQs

Question 9. Node Of Ranvier Is The Place Where :

  1. Myelm Sheath Is Discontinuous
  2. Myelin Sheath And Neurilemma Are Discontinuous
  3. Axolemma Is Absent
  4. Axolemma Is Discontinuous.

Answer: 1. Myelm Sheath Is Discontinuous

Question 10. In The Diagram Of the Section Of the Brain Given Below, Different Parts Are Indicated By Alphabet. Choose The Answer In Which These Alphabets Have Been Correctly Matched With The Parts These Indicate :

 

Nervous System In The Diagram Section Of Brain Question 10.

  1. 1 = Cerebral Hemisphere, 2 = Corpus Callosum, 3 = Thalamus, 4 = Pineal Gland, 5 = Cerebellum, 6 = Pituitary, 7 = Medulla Oblongata.
  2. 1 = Cerebral Hemisphere, 2 = Thalamus, 3 = Corpus Callosum, 4 = Pineal Gland, 5 = Pituitary, 6 = Medulla Oblongata, 7 = Cerebellum.
  3. 1 = Corpus Callosum, 2 = Cerebral Hemisphere, 3 = Pituitary, 4 = Pineal Gland, 5 = Thalamus.
  4. 1 = Cerebral Hemisphere, 2 = Corpus Callosum, 3 = Thalamus, 4 = Pineal Gland, 5 =Pituitary, 6 = Cerebellum, 7 = Medulla Oblongata.

Answer: 4. 1 = Cerebral Hemisphere, 2 = Corpus Callosum, 3 = Thalamus, 4 = Pineal Gland, 5 =Pituitary, 6 = Cerebellum, 7 = Medulla Oblongata.

Question 11. In The Diagram Of T.S. Of The Spinal Cord Given Below, Certain Parts Have Been Indicated By Alphabet. Choose The Answer In Which These Alphabets Have Been Correctly Matched With The Parts Of Which They Indicate :

Nervous System In The Diagram Of T.S Of The Spinal Cord Question 11.

  1. L = Dorsal Septum, 2 = Dorsal Horn, 3 S Grey Matter, 4 = Central Cavity, 5 = White Matter, 6 =Ventral Hom, 7 = Ventral Root, 8 = Dorsal Root And Ganglion ,
  2. 1 = Dorsal Septum, 2 = Dorsal Hom, 3 = Central Cavity, 4 Grey Matter, 5 = Ventral Hom, 6 =White Matter, 7 = Dorsal Root And Ganglion,
  3. 1 = Dorsal Septum, 2i Dorsal Hom, 3 = Grey Matter, 4 =White Matter, 5 = Central Cavity, 6 =Ventral Root, 7 = Dorsal Root And Ganglion
  4. 1 = Dorsal Septum, 2 = Dorsal Hom, 3 = Central Cavity, 4 =Grey Matter, 5 = Ventral Hom, 6 =White Matter, 7 = Dorsal Root And Ganglion 8 = Ventral Root ‘

Answer: 1. L = Dorsal Septum, 2 = Dorsal Horn, 3 S Grey Matter, 4 = Central Cavity, 5 = White Matter, 6 =Ventral Hom, 7 = Ventral Root, 8 = Dorsal Root And Ganglion

Question 12. Which Of The Following Cranial Nerve Controls The Movement Of Eye Ball?

  1. Oculomotor
  2. Optic
  3. Ophthalmic
  4. Trochlear.

Answer: 1. Oculomotor

Question 13. Which Of The Following Is a part Of the Human Brain?

  1. Corpora Bigemina
  2. Corpora Allata
  3. Corpora Adiposa 1
  4. Corpora Quadrigemina.

Answer: 4. Corpora Quadrigemina

Question 14. A Bipolar Neuron Has :

  1. Two Dendrites And One Oxon
  2. One Oxon And One Dendrite
  3. Two Axons And One Dendrite
  4. Two Axons And Two Dendrites.

Answer: 2. One Oxon And One Dendrite

Question 15. These Processes Occur During Repolarization Of Nerve Fibre :

A. Open Na+ Channel

B. Close Na+ Channel

C. Close K+ Channel

D. Open K+ Channel.

  1. B And C
  2. A And C
  3. B And D
  4. A And B.

Answer: 3. B And D

Question 16. Which Of the following Ctamal Naves Are Mixed :

A.  Vagus

B. Trigeminal

C. Glosxopbanngeal

D. Amhtoiy.

Answer Codes :

  1. A, B, And C Are Correct
  2. B And D Are Correct
  3. A And C Are Correct
  4. A And B Are Correct.

Answer: 1. A, B, And C Are Correct

PSEB Class 11 Biology Central Nervous System MCQs

Question 17. Touch On The Right Side Stimulate Neurons On :

  1. Right Somatic Sensory Area
  2. Right Somatic Motor Area
  3. Left Somatic Sensory Area
  4. Both 1 And 3

Answer: 3. Left Somatic Sensory Area

Question 18. Respiratory Centre Of Brain Is Sensitised By :

  1. More Blood To Brain
  2. More Blood In The Lungs
  3. More Co2 Cone, In The Blood
  4. More O2 Cone, In The Blood.

Answer: 3. More Co2 Cone, In The Blood

Question 19. The Point In Eye Of Mammals From Which Optic Nerves And Blood Vessels Leaves The Eye Ball Is :

  1. Yellow Spot
  2. Blind Spot
  3. Pars Optica
  4. None Of These.

Answer: 2. Blind Spot

Question 20. The Primary Visual Area Is Located In :

  1. Frontal Lobe
  2. Parietal Lobe
  3. Temporal Lobe
  4. Occipital Lobe.

Answer: 4. Occipital Lobe

Question 21. Choroid Plexus Is A Network Of :

  1. Nerves
  2. Lymph Vessels
  3. Capillaries
  4. Muscle Fibres.

Answer: 3. Capillaries

Question 22. In The Resting State Of The Neural Membrane, Diffusion Due To Concentration Gradients, If Allowed, Would Drive :

  1. K+ Into The Cell
  2. K+ And Na+ Out Of The Cell
  3. Na+ Into The Cell
  4. Na+ Out Of The Cell.

Answer: 3. Na+ Into The Cell

Question 23. Injury To Vagus Nerve In Humans Is Not Likely To Affect:

  1. Tongue Movements
  2. Gastrointestinal Movements
  3. Pancreatic Secretion
  4. Cardiac Movements.

Answer: 1. Tongue Movements

Question 24. Unidirectional Transmission Of A Nerve Impulse Through Nerve Fibre Is Because:

  1. Nerve Fibre Is Insulated By A Medullary Sheath
  2. Sodium Pump Starts Operating Only At The Cyton And Then Continues Into The Nerve Fibre
  3. Neurotransmitters Are Released By Dendrites And Not By Axon Endings
  4. Neurotransmitters Are Released By The Axon Endings And Not By Dendrites.

Answer: 4. Neurotransmitters Are Released By The Axon Endings And Not By Dendrites.

Question 25. Which Of The Following Is Mixed Nerve?

  1. Glossopharyngeal
  2. Trochlear
  3. Hypoglossal
  4. Oculomotor.

Answer: 1. Glossopharyngeal

Question 26. Four Healthy People In Their Twenties Got Involved In Injuries Resulting In Damage And Death Of A Few Cells Of The Following. Which Of The Cells Are Least Likely To Be Replaced By New Cells?

  1. Ostcocyles
  2. Malpighian Layer Of The Skin
  3. Liver Cells
  4. Neurons.

Answer: 4. Neurons

Question 27. One Of The example of The Action Of The Autonomous Nervous System Is :

  1. Knee-Jerk Response
  2. Pupillary Reflex
  3. Swallowing Of Inod
  4. Peristalsis Of The Intestines.

Answer: 4. Peristalsis Of The Intestines.

Central Nervous System Multiple Choice Questions PSEB Class 11

Question 28. Parkinson’s Disease (Characterized By Tremors And Progressive Rigidity Of Limbs) Is Caused By the degeneration Of Brain Neurons That Are Involved In Movement Control And Make Use Of Neurotransmitters:

  1. Acetylcholine
  2. Norepinephrine
  3. Dopamine
  4. Gaba

Answer: 3. Dopamine

Question 29. In A Man, Abducens Nerve Is Injured. Which One Of The Following Functions Will Be Affected?

  1. Movement Of The Eye Ball
  2. Movement Of The Tongue
  3. Swallowing
  4. Movement Of The Neck.

Answer: 1. Movement Of The Eye Ball

Question 30. You Are Watching A Horror Movie And You Notice Your Heart Is Beating Fast And Mouth Is Dry. It Is Because Of

  1. Fight And Flight Response
  2. Sympathetic Nervous System
  3. Parasympathetic Nervous System
  4. Both 1 And 3

Answer: 4. Both 1 And 3

Question 31. Reflex Action Is Controlled By :

  1. Sympathetic Nervous System
  2. Automatic Nervous System
  3. Spinal Cord
  4. Craniosacral Outflow.

Answer: 3. Spinal Cord

Question 32. Tree Of Life Is :

  1. Arbor Vitae
  2. Pons Varolii
  3. Organ Of Corti
  4. Diencephalon.

Answer: 1. Arbor Vitae

Question 33. Arbor Vitae Is Part Of:

  1. Cerebrum
  2. Cerebellum
  3. Mid Brain
  4. Fore Brain.

Answer: 2. Cerebellum

Question 34. Which Has H – H-Shaped Grey Matter?

  1. Cerebrum
  2. Medulla Oblongata
  3. Cerebellum
  4. Spinal Cord

Answer: 4. Spinal Cord

Central Nervous System Multiple Choice Questions PSEB Class 11

Question 35. Find Out The Correct Answer From The Following Statements. The Main Functions Of The Cerebrum Of the Human Brain Are

A. To Control The Contraction Of Voluntary Muscles Through The Frontal Lobe

B. To Control The Sensitivity, Movement, Memory, Vocabulary Etc. Through The Frontal Lobe

C. To Control The Temperature, Taste, Touch, Pain Etc, Through The Parietal Lobe

D. To Control The Vision And Adaptation Through The Occipital And Frontal Lobes.

Choose The Correct Answer.

  1. A, B, D
  2. C, D, A
  3. A, B, C
  4. B, C, D.

Answer: 1. A, B, D

Question 36. A Diagram Showing the Axon Terminal And Synapse Is Given. Identify Correctly At Least Two Of A-D.

Nervous System In The Diagram Showing Axon Terminal And Synapse Is Given Question 36.

  1. B – Synaptic Connection D – K+
  2. C – Neurtransmitter D – Ca++
  3. A – Neurotransmitter B – Synaptic Cleft
  4. A – Receptor C – Synaptic Vesicles.

Answer: 4. A – Receptor C – Synaptic Vesicles.

Question 37. In Parasympathetic Nervous System Which Of The Following Is Released?

  1. Epinephrine
  2. Nor Epinephrine
  3. Serotonin
  4. Acetylcholine.

Answer: 4. Acetylcholine.

Question 38. Column I Lists The Parts Of The Human Brain And Column Ii Lists The Functions. Match The Two Columns And Identify The Correct Choice From Those Given.

Nervous System Column 1 Lists The Parts Of Human Brain And Column 2 Lists The Function. Question 38

  1. A = T;  B = S ;  C = Q ;  D = P
  2. A = S ; B = T   C = R     D = P
  3. A = T;  B = S ; C = R ;   D = Q
  4. A = S, B = T;  C = P,   D = Q.

Answer: 4. A = S , B = T;  C = P ,   D = Q.

Question 39. Hypothalamus Does Not Control :

  1. Hunger And Satiety
  2. Thermoregulation
  3. Creative Thinking And Consciousness
  4. Osmoregulation.

Answer: 3. Creative Thinking And Consciousness

PSEB Class 11 Biology Chapter CNS MCQs

Question 40. Match The Following Human Spinal Nerves In Column 1 With The Number Of Pairs In Column 2 and Choose The Correct Options.

Nervous System Match The Following Question 40

  1. A – 2, B – 4, C – L,  D-3
  2. A – A, B – 3, C – 1   D -2
  3. A – 3, B – 3  C – 2,  D- A
  4. A – 4, B – 1, C – 2,  D – 3.

Answer: 2. A – A, B – 3, C – 1   D -2

Question 41. The Brachial Plexus Are Formed By These Spinal Nerves:

  1. IV, V, Vi Cervical
  2. V, Vi, Vii, Viii Cervical And Thoracic
  3. IV To Vh Lumbar
  4. First Three Sacral.

Answer: 2. V, Vi, Vii, Viii Cervical And Thoracic

Question 42. Which One Of The Following Does Not Act As A Neurotransmitter?

  1. Epinephrine
  2. Norepinephrine
  3. Cortisone
  4. Acetylcholine.

Answer: 3. Cortisone

Question 43. In The Given Diagram Which Stage Of Conduction Of Nerve Impulse Through Nerve Fibre Is Observed?

Nervous System In The Given Diagram Question 43.

  1. Polarization
  2. Resting Potential
  3. Repolarization
  4. Depolarization.

Answer: 2. Resting Potential

Question 44. How Many Pairs Of Spinal Nerves Are Found In Humans?

  1. 32
  2. 31
  3. 30
  4. 33.

Answer: 2. 31

Question 45. The Decoding And Interpretation Of Visual Information Is Carried Out By Which Part Of The Brain?

  1. Cerebellum
  2. Frontal Lobe
  3. Parietal Lobe
  4. Temporal Lobe
  5. Occipital Lobe.

Answer: 3. Temporal Lobe

Question 46. Match The Entries In Column I With Those In Column Ii And Choose The Correct Combination From The Options Given.

Nervous System Match The Entire Column 1And 2 Question 46.

  1. A-4,  B-3,  C-L,  D-2
  2. A-3,  B-4,  C-1   D-2
  3. A-4,  B-1,  C-2,  D-3
  4. A-1,  B-2,  C-3,  D-A
  5. A-4,  B-1,  C-2,  D-3.

Answer: 3. A-4,  B-1,  C-2,  D-3

Question 47. The Accumulation Of Protein Called Amyloid 3 Peptide In the Human Brain Causes :

  1. Addison’s Disease
  2. Huntington’s Disease
  3. Alzheimer’s Disease
  4. Motor-Neuron Disease
  5. Parkinson’s Disease.

Answer: 3. Alzheimer’s Disease

PSEB Class 11 Biology Chapter CNS MCQs

Question 48. A Typical Value Of Resting Membrane Potential Is :

  1. – 40 Mv
  2. – 60 Mv
  3. – 70 Mv
  4. – 80 Mv
  5. – 90 Mv.

Answer: 2. – 60 Mv

Question 49. Given Below Is A Table Comparing The Effects Of Sympathetic And Parasympathetic Nervous System For Four Features (1-4). Which One Feature Is Correctly Described?

Nervous System Given Below Is A Table Comparing Question 49

Answer: 2. Pupil Of The Eye – Dilate – Constricts

Question 50. Bowman’s Glands Are Located In The :

  1. Anterior Pituitary
  2. Female Reproductive System Of Cockroach
  3. Olfactory Epithelium Of Our Nose
  4. Proximal End Of Uriniferous Tubules.

Answer: 3. Olfactory Epithelium Of Our Nose

Question 51. During The Transmission Of Nerve Impulse Through A Nerve Fibre, The Potential On The Inner Side Of The Plasma Membrane Has Which Type Of Electric Charge?

  1. First Positive, Then Negative, And Continue To Be Negative
  2. First Negative, Theh ‘Positive And Continue To Be Positive
  3. First Positive, Then Negative, And Again Back To Positive
  4. First Negative, Then Positive, And Again Back To Negative

Answer: 4. First Negative, Then Positive, And Again Back To Negative

Question 52. During The Propagation Of A Nerve Impulse, The Action Potential Results From The Movement Of :

  1. K+ Ions From Intracellular Fluid To Extracellular Fluid
  2. Na+ Ions From Extracellular Fluid To Intracellular Fluid
  3. K+ Ions From Extracellular Fluid To Extracellular Fluid
  4. Na+ Ions From Intracellular Fluid To Extracellular Fluid.

Answer: 2. Na+ Ions From Extracellular Fluid To Intracellular Fluid

Question 53. The Potential Maintained Across The Neuron Membrane During The Resting State Is :

  1. + 70 Mv
  2. – 70 Mv
  3. 0.5 V
  4. – 30 Mv
  5. + 30 Mv

Answer: 2. – 70 Mv

Question 54. A Person Entering An Empty Room Suddenly Finds A Snake Right In Front On Opening The Door. Which One Of The Following Is Likely To Happen In His Neuro-Hormonal Control System?

  1. Neurotransmitters Diffuse Rapidly Across The Cleft And Transmit A Nerve Impulse.
  2. The Hypothalamus Activates The Parasympathetic Division Of the Brain.
  3. The sympathetic Nervous System Is Activated Releasing  Epinephrine And Norepinephrine From the Adrenal Cortex.
  4. The sympathetic Nervous System Is Activated Releasing Epinephrine And Norepinephrine From Adrenal Medulla.

Answer: 4. The Sympathetic Nervous System Is Activated Releasing Epinephrine And Norepinephrine From the Adrenal Medulla.

Question 55. The Human Hind Brain Comprises Three Parts, One Of Which Is :

  1. Corpus Callosum
  2. Cerebellum
  3. Hypothalamus
  4. Spinal Cord.

Answer: 2. Cerebellum