If atmospheric CO2 concentrations increase two fold or more, how will plants be affected, disregarding any changes in the climate?
1.
All plants will experience increase in photosynthesis
2.
C3 plants will have faster growth, C4 plants will be minimally affected
3.
C4 plants will have faster growth, C3 plants will be minimally affected
4.
Plants growth will not affected because atmospheric CO2 concentrations are never limiting for plant growth
Subtopic: Â C4 Cycle (Hatch & Slack Pathway) |
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The plant factor affecting photosynthesis is :
1. Amount of chlorophyll
2. Sunlight
3. Soil water
4. All of these
1. Amount of chlorophyll
2. Sunlight
3. Soil water
4. All of these
Subtopic: Â Factors Affecting Photosynthesis |
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In a plant system, the rate of photosynthesis may become equal to the rate of respirational at ;
1. CO2 compensation point
2. Light compensation point
3. Light saturation point
4. More than one option is correct
1. CO2 compensation point
2. Light compensation point
3. Light saturation point
4. More than one option is correct
Subtopic: Â Factors Affecting Photosynthesis |
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Observe the graph given below and choose the correct option:
| 1. | Light is a limiting factor at the region marked A |
| 2. | At the point D of light intensity, the rate of photosynthesis is maximum |
| 3. | Both (1) and (2) |
| 4. | The region marked C shows continuous increase in the rate of photosynthesis |
Subtopic: Â Factors Affecting Photosynthesis |
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The primary acceptor of CO2 in C3 cycle and C4 cycle are respectively :
1. RuBP and PEP
2. PEP and RuBP
3. 3-PGA and PEP
4. RuBP and 3-PGA
1. RuBP and PEP
2. PEP and RuBP
3. 3-PGA and PEP
4. RuBP and 3-PGA
Subtopic: Â C4 Cycle (Hatch & Slack Pathway) |
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To synthesis one molecule of glucose the requirements of CO2 : ATP : NADPH + H+ in C3 plants are C4 plants are :
| C3 Plant CO2 : ATP : NADPH + H+ |
C4 Plant CO2 : ATP : NADPH + H+ |
|
| 1. 2. 3. 4. |
6 : 30 :12 1 : 5 : 2 6 :18 :12 1 : 3 : 2 |
6 :18 : 12 1 : 3 : 2 6 : 30 : 12 1 : 5 : 2 |
Subtopic: Â C4 Cycle (Hatch & Slack Pathway) |
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How is photosynthesis similar in C4 plants and CAM plants?
| 1. | Both uses only PS-I |
| 2. | Both makes sugar without C3 cycle |
| 3. | In both cases, initial carboxylation does not involve RuBisCO |
| 4. | Both possess agranal chloroplast only |
Subtopic: Â C4 Cycle (Hatch & Slack Pathway) |Â CAM Pathway |
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| Assertion(A) : | Plants possessing C4 -pathway of carbon fixation have a higher net primary productivity than the C3 -pathway possessing plants. |
| Reason(R) : | For each unit weight of fixed carbon, C4 -pathway possessing plants require less water than C3 -pathway possessing plants. |
| 1. | Both assertion and reason are true and the reason is the correct explanation of assertion. |
| 2. | Both assertion and reason are true but the reason is not the correct explanation of assertion. |
| 3. | If assertion is true but the reason is false. |
| 4. | If both assertion and reason are false statements. |
Subtopic: Â C4 Cycle (Hatch & Slack Pathway) |
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Given below are two statements:
| Assertion (A): | The absorption spectrum of chlorophyll-\(\alpha\) shows close correlation with its action spectrum |
| Reason (R): | Chlorophyll-\(\alpha\) is present in both PS-I and PS-II |
| 1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
| 2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
| 3. | (A) is True but (R) is False. |
| 4. | Both (A) and (R) is False. |
Subtopic: Â Photosynthetic Pigments |Â Photosystems |
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Assertion(A) : The atmospheric concentration of CO2 at which photosynthesis just compensates for respiration is referred to as CO2 compensation point.
Reason(R) : The CO2 compensation point in reached when the amount of CO2 uptake is less than that generated through respiration because the level of CO2 in the atmosphere is more than that required for achieving CO2 compensation point.
Reason(R) : The CO2 compensation point in reached when the amount of CO2 uptake is less than that generated through respiration because the level of CO2 in the atmosphere is more than that required for achieving CO2 compensation point.
1. Both assertion and reason are true and the reason is the correct explanation of assertion.
2. Both assertion and reason are true but the reason is not the correct explanation of assertion.
3. If assertion is true but the reason is false.
4. If both assertion and reason are false statements.
Subtopic: Â Photorespiration |
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