AP Biologyeasymcq1 pt
During the light reactions, water is split to
A.replace electrons lost by photosystem II and release O₂
B.provide carbon for glucose
C.make NADPH directly from H₂O
D.cool the chloroplast
Explanation
Core Concept
Photolysis at photosystem II supplies electrons to the chain, releasing oxygen as a byproduct. The H⁺ also feeds the proton gradient.
Correct Answer
Areplace electrons lost by photosystem II and release O₂
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