Dark reactions of photosynthesis are actually not totally independent of light as:
(1) The initial reactions occur in the presence of light.
(2) The reaction will be inhibited by the presence of light.
(3) They can occur during the day as well.
(4) They utilize the products of the light reaction.
Dark reaction occurs
(1) only in light
(2) only in the absence of light
(3) independent of light
(4) both (1) and (3).
Photosynthesis in C4 plants is relatively less limited by atmospheric CO2 levels because
(1) there is effective pumping of CO2 into bundle sheath cells
(2) RuBisCO in C4 plants has higher affinity for CO2
(3) six carbon acids are the primary initial CO2 fixation products
(4) the primary fixation of CO2 is mediated via PEP carboxylase.
In Kranz anatomy, the bundle sheath cells have
(1) thin walls, many intercellular space and no chloroplast
(2) thick walls, no intercellular spaces and large number of chloroplasts
(3) thin walls, no intercellular spaces and several chloroplasts
(4) thick walls, many intercellular space and few chloroplasts
The C4 plants differ from C3 plants with reference to the:
1. substrate that accepts CO2 in carbon assimilation
2. type of end product
3. type of pigment involved in photosynthesis
4. end product that will be formed
How many of the following statements are correct?
i. Products of dark reaction are substrates of light reaction.
ii. Products of light reaction are substrates of dark reaction.
iii. In the stroma, enzymatic reactions incorporate CO2 into the plant leading to the synthesis of sugar.
iv. Dark reactions are directly light-driven.
v. Chloroplast is a single membranous organelle.
1. 2
2. 3
3. 4
4. 1
ATP and NADPH produced during photosynthesis, are used in which of the following reactions?
a. Catabolic
b. Biosynthetic phase
c. amphibolic
d. Hydrolytic phase
The net requirement of assimilatory power for the formation of 6 hexose molecules in maize plant is:
1. 72 ATP, 48 NADPH
2. 90 ATP, 60 NADPH
3. 108 ATP, 72 NADPH
4. 180 ATP, 72 NADPH
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.
Assertion (A): | Six molecules of CO2 and twelve molecules of NADPH + H+ and 18 ATP are used to form one hexose molecules. |
Reason (R): | Light reaction results in formation of ATP and NADPH2. |
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) are false. |