I: | Current availability of carbon dioxide levels is limiting to the C4 plants. |
II: | C3 plants have a much lower temperature optimum than C4 plants. |
1. | Only I is correct | 2. | Only II is correct |
3. | Both I and II are correct | 4. | Both I and II are incorrect |
COLUMN I | COLUMN II | ||
A | Jan Ingenhousz | P | Provided evidence for production of glucose when plants grow |
B | T. W Engelmann | Q | Described the first action spectrum for photosynthesis |
C | Julius von Sachs | R | Showed that sunlight is essential for photosynthesis |
D | Cornelius van Neil | S | Inferred that oxygen evolved in photosynthesis comes from water and not from carbon dioxide |
A | B | C | D | |
1. | R | Q | P | S |
2. | Q | R | S | P |
3. | P | S | R | Q |
4. | S | P | Q | R |
I: | include chlorophyll b, xanthophylls and carotenoids. |
II: | absorb light and transfer electrons to chlorophyll a. |
III: | protect chlorophyll a from photo-oxidation. |
1. | Only I | 2. | Only I and III |
3. | Only II and III | 4. | Only IV |
1. | Chlorophyll a is the chief pigment associated with photosynthesis. |
2. | Splitting of water is associated with PS II |
3. | Cyclic flow of electrons results only in the synthesis of NADH |
4. | Biosynthetic phase is dependent on the products of the light reaction |
I: | Calvin cycle takes place in Bundle sheath cells |
II: | Number of carbon atoms in the primary carbon dioxide acceptor is 5 |
III: | Initial carboxylation reaction occurs in mesophyll cells |
IV: | Primary carbon dioxide fixation product is oxaloacetic acid |
1. | Only I, II and III | 2. | Only I, III and IV |
3. | Only II, III and IV | 4. | I, II, III and IV |
Feature | C3 Plant | C4 Plant | |
1. | Cell type in which Calvin cycle takes place | Mesophyll cells | Bundle sheath cells |
2. | Cell type in which the initial carboxylation reaction occurs | Bundle sheath cells | Mesophyll cells |
3. | Primary carbon dioxide acceptor | RuBP | PEP |
4. | Number of carbons in the primary carbon dioxide fixation product | 5 | 3 |
I: | The reaction centre chlorophyll a in PS I is called P700 |
II: | Oxygen evolving complex is associated with PS II |
III. | Both ATP and NADPH are made during cyclic photophosphorylation |
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 |
1. | Cornelius van Neil | Oxygen evolved comes from water |
2. | T W Engelmann | First absorption spectrum of chlorophyll a |
3. | Joseph Priestley | Plants restore to the air whatever breathing animals remove |
4. | Jan Ingenhousz | Sunlight is essential for photosynthesis |
1. | There is a linear relationship between incident light and carbon dioxide fixation rates at low light intensities. |
2. | Current availability of carbon dioxide levels is limiting to the C4 plants. |
3. | C4 plants respond to higher temperatures and show higher rates of photosynthesis |
4. | Water stress causes the stomata to close, hence reducing the availability of carbon dioxide |