本题目来源于试卷: Interaction & Interdependence C.3 Photosynthesis，类别为 IB生物学
[单选题]
What is used to generate a proton gradient acros t- jgoecba **4tn.a*js the thylakoid membranef;m 1(np a)hpi in the light-dependent reactions of photosy n(a)ph;f 1pminthesis?
A. Triose phosphate
B. Electrons from Photosystem II
C. ATP synthase
D. Reduced NADP
参考答案: B
本题详细解析:
B Excited electrons from Photosystem II release energy which causes protons to be pumped across the thylakoid membrane generating a proton gradient. The ATP synthase (Choice C) in thylakoids does not generate a proton gradient, but instead uses the proton gradient to generate ATP. Excited electrons from Photosystem I are then used to reduce NADP. The reduced NADP (Choice D) is not used to generate a proton gradient, but instead provides hydrogen atoms to reduce glycerate 3-phosphate to triose phosphate. Triose phosphate (Choice A) is then used to regenerate ribulose bisphosphate (RuBP) and produce carbohydrates.
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