Q. No.The order of the three steps of Calvin cycle is-
| 1. | Carboxylation- Reduction-Regeneration |
| 2. | Reduction-Regeneration- Carboxylation |
| 3. | Regeneration-Carboxylation- Reduction |
| 4. | Reduction- Carboxylation –Regeneration |
For the formation of one molecule of Glucose, how many turns of fixation are required?
| 1. | 3 | 2. | 2 |
| 3. | 6 | 4. | 4 |
Melvin-Calvin used ------- radioactive in-----studies for the discovery of first CO2 fixation product.
| 1. | 14C , Fungal photosynthesis |
| 2. | 14C , Algal photosynthesis |
| 3. | 15N , Fungal photosynthesis |
| 4. | 15N , Algal photosynthesis |
Dark reaction depends upon-
| 1. | Presence of darkness |
| 2. | Presence of light |
| 3. | Products of light reactions |
| 4. | Products of biosynthetic phase |
The first dark reaction or CO2 fixation product is-
| 1. | 3C – Organic Acid | 2. | 6C – Organic Acid |
| 3. | 5C – Organic Acid | 4. | 1C – Organic Acid |
Which of the following statements is incorrect?
| 1. | RuBisCO is a bifunctional enzyme |
| 2. | In C4 plants, the site of RuBisCO activity is mesophyll cell |
| 3. | The substrate molecule for RuBisCO activity is a 5-carbon compound |
| 4. | RuBisCO action requires ATP and NADPH |
The synthesis of one molecule of glucose during the Calvin cycle requires.
| 1. | 12 molecules of ATP and 18 molecules of NADPH2 |
| 2. | 6 molecules of ATP and 12 molecules of NADPH2 |
| 3. | 18 molecules of ATP and 12 molecules of NADPH2 |
| 4. | 12 molecules of each of ATP and NADPH2 |
How many molecules of 3-PGA are produced during a single run of carboxylation?
1. 3
2. 1
3. 2
4. 4
If there are 12 molecules of CO2 to be fixed in photosynthesis, then how many turns of the Calvin cycle and how many molecules of glucose will be synthesized respectively?
1. 9 turns, 2 molecules.
2. 12 turns, 1 molecule.
3. 6 turns, 1 molecule.
4. 12 turns, 2 molecules.
Match the following columns and select the correct option.
| Column-I | Column-II |
| a. Photolysis of water | (i) C plants |
| b. Carboxylation of RuBP | (ii) Non-cyclic photophosphorylation |
| c. Synthesis of ATP only | (iii) Cyclic photophosphorylation |
| d. Consumption of 5 ATP per CO2 fixed |
(iv) Calvin cycle |
| 1. | a (ii), b (iv), c (iii), d (i) |
| 2. | a (iii), b (iv), c (ii), d (i) |
| 3. | a (ii), b (i), c (iii), d (iv) |
| 4. | a (iii), b (i), c (ii), d (iv) |
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