Questions: What will most likely happen to a plant that does not receive enough CO2 ? A. The Calvin cycle will produce less glucose. B. The light reactions will occur faster. C. The Calvin cycle will increase production of glucose. D. The light reactions will stop absorbing light energy.

The answer is A: The Calvin cycle will produce less glucose.

Explanation for each option:

A. The Calvin cycle will produce less glucose.

• This is correct. The Calvin cycle requires carbon dioxide (CO₂) to produce glucose. If a plant does not receive enough CO₂, the Calvin cycle will have less substrate to work with, resulting in reduced glucose production.

B. The light reactions will occur faster.

• This is incorrect. The light reactions are primarily dependent on light energy, not CO₂. A lack of CO₂ does not affect the speed of the light reactions.

C. The Calvin cycle will increase production of glucose.

• This is incorrect. Without sufficient CO₂, the Calvin cycle cannot increase glucose production; it will decrease instead.

D. The light reactions will stop absorbing light energy.

• This is incorrect. The light reactions are driven by light energy, and they will continue to absorb light as long as it is available, regardless of CO₂ levels.

In summary, a plant that does not receive enough CO₂ will most likely experience a decrease in glucose production during the Calvin cycle.