Significance of C4 Pathway

Q.

In Kranz anatomy, bundle sheath cells have

1. thick walls, no intercellular spaces and a large number of chloroplasts

2. thick walls, no intercellular spaces and no chloroplasts

3. thin walls, many intercellular spaces and a large number of chloroplasts

4. thin walls, many intercellular spaces and no chloroplasts

Q.

What is the full form of RuBisCO?

Q.

Even though a very few cells in a $C_4$ plant carry out the biosynthetic – Calvin pathway, yet they are highly productive. Can you discuss why?

Q.

Where do the carbon fixation reactions take place in prokaryotes?

Q. Photorespiration does not occur in $C_4$ plants because

1. of enzyme RuBisCO
2. the first primary acceptor is phosphoenolpyruvate
3. they do not require $C{O}_2$
4. they have a mechanism that increases the concentration of $C{O}_2$ at the enzyme site

Q. In $C_4$-plants, photosystem II is absent in chloroplasts of

1. Mesophyll cells
2. Bundle sheath cells
3. Palisade cells
4. Spongy cells.

Q. Is CO2 a limiting factor at normal concentration in the atmosphere in C4 plants?

Q. Which one of the following have high CO2 compensation point?

1. C3 plants
2. C2 plants
3. C4 plants
4. Herbs

Q. Explain the carbon cycle with the help of a simplified model.

Q.

Outline salient features of carbon cycling in an ecosystem

Q.

What Is RuBisCO in the Calvin cycle?

Q. Peat moss is obtained from

1. Polytrichum
2. Funaria
3. Sphagnum
4. Marchantia

Q.

Do C4 plants use Rubisco?

Q. $C_4$ plants are more efficient in photosynthesis than $C_3$ plants due to

1. presence of larger number of chloroplasts in the leaf cells
2. higher leaf area
3. presence of thin cuticle
4. lower rate of photorespiration

Q. $C_4$ plants are more efficient in photosynthesis than $C_3$ plants due to

1. Lower rate of photorespiration.
2. Higher leaf area.
3. Presence of larger number of chloroplasts in the leaf cells.
4. Presence of thin cuticle.

Q. Photorespiration does not occur in $C_4$ plants because

1. of enzyme RuBisCO
2. the first primary acceptor is phosphoenolpyruvate
3. they do not require $C{O}_2$
4. they have a mechanism that increases the concentration of $C{O}_2$ at the enzyme site

Q. Assertion :Efficiency of $C_4$ plants is more than that of $C_3$ plants. Reason: $C_4$ plants are more efficient in capturing $C{O}_2$.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q. The C4 plants are photosynthetically more efficient than C3 plants because

1. They have more chloroplasts
2. The carbon dioxide compensation point is more
3. Carbon dioxide generated during photorespiration is trapped and recycled through PEP carboxylase
4. The carbon dioxide efflux is not prevented

Q. The green, multicellular, asexual buds are

1. gemmae cups
2. rhizoids
3. foliose
4. protonema

Q. Choose the correct statement regarding bryophytes:

1. The arrangement of leaves in mosses and liverworts is spiral and in two rows, respectively
2. The liverworts are of two types: thallose and prostrate
3. The rhizoids in mosses and liverworts are unicellular and multicellular, respectively
4. The juvenile sporophyte developed from the zygote is known as protonema

Q. Electrons from excited chlorophyll molecules of photosystem II are accepted first by

1. Ferredoxin
2. Pheophytin
3. Cytochrome b
4. Cytochrome f

Q. Primary acceptor of carbon dioxide during photosynthetic in $C_4$ plants is

1. PGA
2. RubP
3. PEP
4. OAA

Q. A : Bryophyta, in general, are of little ecological importance.
B. Mosses reduce the impact of falling rain.

1. A is correct but B is incorrect
2. A is incorrect but B is correct
3. Both A and B are incorrect
4. Both A and B are correct

Q. The role of rhizoids in bryophytes are:

1. Absorption of minerals
2. Absorption of water
3. Anchorage
4. All of the above

Q. Agranal chloroplasts occur in

1. Succulent plants.
2. $C_3$ plants.
3. $C_4$ plants.
4. Hydrophytes.

Q. Which one of the following have high CO2 compensation point?

1. C3 plants
2. C2 plants
3. C4 plants
4. Herbs

Q. Assertion :Submerged plants get carbon dioxide in the form of carbonates and bicarbonates. Reason: Stomata are not present in submerged plants.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q. Assertion :Rhoeo leaves contain anthocyanin pigments in epidermal cells Reason: Anthocyanins are accessory photosynthetic pigments

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q. Sugarcane shows high efficiency of $C{O}_2$ fixation because of

1. Hatch and Slack cycle
2. Greater sunlight
3. TCA cycle
4. Calvin cycle

Q. Assertion : Higher concentration of $O_2$ is inhibitory to photosynthesis. Reason: This inhibition is due to Warburg effect.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect