Q. No.When the ratio, CO2 : O2 is nearly equal, RuBisCO:
1. has no affinity for oxygen
2. has a much greater affinity for carbon dioxide
3. has a much greater affinity for oxygen
4. has equal affinity for both carbon dioxide and oxygen
1. has no affinity for oxygen
2. has a much greater affinity for carbon dioxide
3. has a much greater affinity for oxygen
4. has equal affinity for both carbon dioxide and oxygen
Subtopic: Photorespiration |
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Level 1: 80%+
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In photorespiration, RuBisCO:
1. adds carbon dioxide to RuBP
2. gets denatured
3. adds oxygen to RuBP
4. acquires a very high affinity for carbon dioxide
1. adds carbon dioxide to RuBP
2. gets denatured
3. adds oxygen to RuBP
4. acquires a very high affinity for carbon dioxide
Subtopic: Photorespiration |
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Level 2: 60%+
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RuBisCO:
| I: | is the most abundant enzyme in the world |
| II: | is characterised by the fact that its active site can bind to both CO2 and O2 |
| III: | has a much greater affinity for CO2 when the CO2: O2 is nearly equal |
| 1. | Only I and II are correct |
| 2. | Only I and III are correct |
| 3. | Only II and III are correct |
| 4. | I, II and III are correct |
Subtopic: Photorespiration |
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Level 1: 80%+
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The 2-carbon compound formed in photorespiration is:
| 1. | Acetyl CoA | 2. | Phosphoglycolate |
| 3. | Acetic acid | 4. | Ethanol |
Subtopic: Photorespiration |
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Level 1: 80%+
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In the photorespiratory pathway:
| I: | there is no synthesis of sugars |
| II: | there is release of carbon dioxide with the utilization of ATP |
| III: | ATP is synthesized but NADPH is not synthesized |
| 1. | Only I and II are correct |
| 2. | Only I and III are correct |
| 3. | Only II and III are correct |
| 4. | I, II and III are correct |
Subtopic: Photorespiration |
81%
Level 1: 80%+
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Photorespiration is a wasteful process. Why is it so?
| 1. | The number of ATP molecules produced in the pathway is very low. |
| 2. | The number of NADPH molecules produced in the pathway is very low. |
| 3. | The synthesis of sugars in the pathway requires a large input of ATP energy. |
| 4. | There is neither synthesis of sugars, nor of ATP in the pathway. |
Subtopic: Photorespiration |
88%
Level 1: 80%+
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The greatest problem with photorespiration is faced by:
| 1. | C4 plants | 2. | C3 plants |
| 3. | CAM plants | 4. | purple sulfur bacteria |
Subtopic: Photorespiration |
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Level 1: 80%+
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The process of photosynthesis has lower efficiency if photorespiration occurs because of the reduced formation of:
| 1. | AcetylCoA | 2. | 3-phosphoglycerate |
| 3. | ATP | 4. | RuBP |
Subtopic: Photorespiration |
63%
Level 2: 60%+
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Consider the two statements:
| Statement I: | In C4 plants, photorespiration does not occur. |
| Statement II: | C4 plants have a mechanism that increases the concentration of CO2 at the RuBisCO enzyme site. |
| 1. | Statement I is correct; Statement II is correct |
| 2. | Statement I is incorrect; Statement II is correct |
| 3. | Statement I is correct; Statement II is incorrect |
| 4. | Statement I is incorrect; Statement II is incorrect |
Subtopic: Photorespiration |
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Level 1: 80%+
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What will not be true for C4 plants when compared to C3 plants?
| 1. | They have a special type of leaf anatomy |
| 2. | They tolerate higher temperatures |
| 3. | They show a response to very low light intensities |
| 4. | They lack a process called photorespiration |
Subtopic: Photorespiration | Factors Affecting Photosynthesis | Light Reactions :1 | Light Reactions :2 | Light Reactions :3 |
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