A farmer in Kenya grows maize crops. During a period of drought, the rate of photosynthesis in the maize plants decreases. Which of the following best explains why lack of water reduces the rate of photosynthesis?

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Question

A farmer in Kenya grows maize crops. During a period of drought, the rate of photosynthesis in the maize plants decreases. Which of the following best explains why lack of water reduces the rate of photosynthesis?

Accepted Answer

stomata close to reduce water loss, preventing carbon dioxide from entering the leaf — Award 1 mark for B. This correctly links water stress to stomatal closure and reduced CO₂ availability. A is incorrect because water is a raw material for photosynthesis. C is incorrect because oxygen diffuses out through stomata, and water is not needed for this transport. D is incorrect because water shortage does not increase chlorophyll production.

Answer

water is not a raw material for photosynthesis

Answer

stomata close to reduce water loss, preventing carbon dioxide from entering the leaf

Answer

water is needed to transport oxygen out of the leaf

Answer

lack of water causes the plant to produce more chlorophyll

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