Question 37
Explain how during light reaction of photosynthesis, ATP synthesis is a chemiosmotic phenomenon.
Question 37
Explain how during light reaction of photosynthesis, ATP synthesis is a chemiosmotic phenomenon.
In light reaction, plants trap solar radiation by photosynthetic pigments which convert light energy into chemical energy. The main event of light reaction is photophosphorylation, i.e., the formation of ATP from ADP + Pi by using the energy of excited electron movement through the electron transport chain, present in the thylakoid membrane.
Chemiosmosis is the movement of ions across a selectively permeable membrane, down the electrochemical / proton gradient.
Chemiosmosis hypothesis of ATP formation was first proposed by Mitchell (1961) according to which the enzyme ATP synthase generates ATP via a membrane, proton pump and proton gradient. ATP synthase allows ions O2 protons to pass through membrane and proton pump.
This creates a high concentration of protons (H+) in the lumen and hence diffuses across the membrane to activate ATP ase, releasing ATP molecules. One molecule of ATP is released for every two (H+) ions passing through ATPase.
In light reaction, plants trap solar radiation by photosynthetic pigments which convert light energy into chemical energy. The main event of light reaction is photophosphorylation, i.e., the formation of ATP from ADP + Pi by using the energy of excited electron movement through the electron transport chain, present in the thylakoid membrane.
Chemiosmosis is the movement of ions across a selectively permeable membrane, down the electrochemical / proton gradient.
Chemiosmosis hypothesis of ATP formation was first proposed by Mitchell (1961) according to which the enzyme ATP synthase generates ATP via a membrane, proton pump and proton gradient. ATP synthase allows ions O2 protons to pass through membrane and proton pump.
This creates a high concentration of protons (H+) in the lumen and hence diffuses across the membrane to activate ATP ase, releasing ATP molecules. One molecule of ATP is released for every two (H+) ions passing through ATPase.
