A student increases the light intensity on a plant but the rate of photosynthesis stops increasing. Which factor is most likely limiting the rate?

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Question

A student increases the light intensity on a plant but the rate of photosynthesis stops increasing. Which factor is most likely limiting the rate?

Accepted Answer

The concentration of carbon dioxide in the air — When increasing light intensity no longer raises the photosynthesis rate, another factor must be limiting — most commonly carbon dioxide concentration at normal atmospheric levels (~0.04%). Chlorophyll content is relatively constant and not typically the immediate limiting factor in this scenario. Oxygen is a product of photosynthesis, not a reactant, so its concentration does not limit the rate. Wavelength affects efficiency but is not the classic limiting factor described here.

Answer

The amount of chlorophyll in the leaf

Answer

The concentration of oxygen around the plant

Answer

The concentration of carbon dioxide in the air

Answer

The wavelength of the light being used

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