Biology 9700 · AS & A Level · Photosynthesis as an energy transfer process

Photosynthesis as an energy transfer process — practice question

Part B Answer one question.

(a)[7]

Describe and explain how guard cells bring about stomatal opening.

(b)[8]

Explain how the anatomy and physiology of the leaves of maize or sorghum enable carbon dioxide fixation to be maximised at high temperatures.

Worked solution & mark scheme

This 15-mark question has a full step-by-step worked solution and mark scheme. One marking point: “$H^+$ pumps in the guard cell membrane” …