Question

What is chemiosmotic hypothesis?

Answer 1

1. The chemiosmotic hypothesis was proposed by Dr. Peter Mitchell in the year 1961.
2. Chemiosmosis is the movement of ions down the electrochemical gradient across a selectively permeable membrane.
3. It plays an important role in the generation of ATP during photosynthesis (inside chloroplasts) and respiration (inside mitochondria).
4. In both these processes, ATP is generated by movement of H+ ions (protons) across a membrane.
5. When H+ ions (protons) diffuse from an area of higher concentration to lower concentration, an electrochemical gradient of protons is established.
6. According to the chemiosmotic hypothesis, it is this electrochemical gradient of protons coupled with the influence of ATP synthetase enzyme that is responsible for the generation of ATP.

[Image Reference : http://www.uwyo.edu/botany4400/photosyn13.gif]