The reactions of Calvin cycle not directly dependent on light, but they usually do not occur at night. Why?

Question

The reactions of Calvin cycle not directly dependent on light, but they usually do not occur at night. Why? (A) Night is often too cold for these reactions to occur. (B) CO 2 concentration in night is too high for these reactions to occur. (C) Plants usually open their stomata at night. (D) Calvin cycle is dependent on the products of light reaction.

Tardigrade Admin · Accepted Answer

Calvin cycle that take place in stroma of the chloroplasts during photosynthesis, is light-independent. But they usually do not occur in night because this cycle is dependent on the products of the light reactions. The Calvin cycle proceeds in three stages: carboxylation [ CO 2. is covalently linked to a carbon skeleton (RuBP)], reduction (carbohydrate is formed at the expense of ATP and NADPH ) and regeneration (the CO 2 acceptor RuBP reforms at the expense of ATP.

Q. The reactions of Calvin cycle not directly dependent on light, but they usually do not occur at night. Why?

Night is often too cold for these reactions to occur.

$C O_{2}$ concentration in night is too high for these reactions to occur.

Plants usually open their stomata at night.

Calvin cycle is dependent on the products of light reaction.

Q. The reactions of Calvin cycle not directly dependent on light, but they usually do not occur at night. Why?

Night is often too cold for these reactions to occur.

CO2​ concentration in night is too high for these reactions to occur.

Plants usually open their stomata at night.

Calvin cycle is dependent on the products of light reaction.

$C O_{2}$ concentration in night is too high for these reactions to occur.