Question

What is the source of electrons that replace lost electrons from the photosystems during photosynthesis and what is their final destination in photosynthesis?

Answer 1

During the light reaction, PSII lost its electron due to excitation by sunlight. During excitation, it loses an electron. At the same time photolysis of water takes place in the vicinity of PSII. During photolysis of water, electrons, proton and molecular oxygen are generated. Electrons are transferred to PSII. Electron passes through a series of the electron transport chain and ultimately accepted by NADP+ which get reduced to NADPH.

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