What is photolysis in photosynthesis?

Photolysis in photosynthesis specifically refers to the splitting of water molecules into oxygen, protons, and electrons when light energy is absorbed. This process occurs in the thylakoid membranes of chloroplasts during the light-dependent reactions of photosynthesis.

When chlorophyll and other pigments absorb light, they become energized and facilitate the photolysis of water. This reaction not only produces oxygen as a byproduct, which is released into the atmosphere, but also provides the necessary electrons for the electron transport chain, ultimately leading to the production of ATP and NADPH, which are crucial for the subsequent light-independent reactions (Calvin cycle) where glucose is synthesized.

Understanding photolysis is fundamental in recognizing how light energy is transformed into chemical energy in plants and how oxygen is generated as a byproduct.