In the C4 pathway, which of the following molecules combines with carbon dioxide?
1. glyceraldehyde phosphate
2. ribulose biphosphate
3. phosphoenol pyruvic acid
4. citric acid
Crops such as tomatoes and bell pepper, allowed to grow in a carbon dioxide rich environment, show higher yields because:
| 1. | They show an increased rate of photosynthesis at higher carbon dioxide concentrations. |
| 2. | They can respond to high carbon dioxide conditions even in low light conditions. |
| 3. | They show C4 pathway for carbon fixation at high carbon dioxide is the limiting factor in such plants. |
| 4. | Only carbon dioxide is the limiting factor in such plants. |
A plant in your garden avoids photorespiratory losses, has improved water use efficiency, shows high rates of photosynthesis at high temperatures and has improved efficiency of nitrogen utilization. In which of the following physiological groups would you assign this plant?
1. C4
2. CAM
3. Nitrogen-fixer
4. C3
C4 -plants are more efficient in photosynthesis than C3 -plants due to
| 1. | higher leaf area |
| 2. | presence of larger number of chloroplasts in the leaf cells. |
| 3. | presence of thin cuticle |
| 4. | lower rate of photorespiration |
The C4 -plants are photosynthetically more efficient than C3 -plants because
| 1. | the CO2 compensation point is more |
| 2. | CO2 generated during photorespiration is trapped and recycled through PEP carboxylase |
| 3. | the CO2 efflux is not prevented |
| 4. | they have more chloroplasts. |
In the leaves of C4 -plants malic acid synthesis during CO2 fixation occurs in
(1) epidermal cells
(2) mesophyll cells
(3) bundle sheath
(4) guard cells
The C4 plants grow very efficiently in warm climates because they
| 1. | consume fewer ATP molecules for glucose synthesis |
| 2. | minimize photorespiratory losses |
| 3. | have more efficient chloroplasts |
| 4. | contain enzymes which are not inactivated at high temperatures. |
Kranz anatomy is usually associated with
| 1. | C3 plants |
| 2. | C4 plants |
| 3. | CAM plants |
| 4. | C3-C4 intermediate plants. |
C4 plants have better productivity because
| 1. | C4 plants absorb more light |
| 2. | C4 plants absorb more CO2 |
| 3. | C4 plants does not carry photorespiration |
| 4. | C4 plants have more amount of RuBisCO. |
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