A scientist investigates the effect of light intensity on the rate of photosynthesis in pondweed. At very high light intensities, the rate of photosynthesis stops increasing. What is the most likely reason for this?

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Question

A scientist investigates the effect of light intensity on the rate of photosynthesis in pondweed. At very high light intensities, the rate of photosynthesis stops increasing. What is the most likely reason for this?

Accepted Answer

B) Another factor, such as carbon dioxide concentration, has become limiting — When the rate of photosynthesis plateaus despite increasing light intensity, a different factor — most commonly carbon dioxide concentration or temperature — has become the limiting factor. Chlorophyll is not destroyed or depleted by high light intensity under normal experimental conditions.

Answer

B) Another factor, such as carbon dioxide concentration, has become limiting

Answer

A) The plant runs out of chlorophyll at high light intensities

Answer

D) High light intensity causes stomata to close, stopping all gas exchange

Answer

C) Excess light destroys the glucose produced by photosynthesis

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