Describe the process of cyclic photophosphorylation?

Inside a chloroplast, there are thylakoid disks, that have their own phospholipid bilayer membrane, which contains embedded protiens, which allow the process of cyclic ad non-cyclic photophosphorylation to happen. Cyclic photophosphorylation is a cycle where the electron is recycled. One of the components in the thylakoid membrane is a photosystem, which is packed with chlorophyl. The chlorophyl absorbs the light energy and uses it to excite the electron. The electron is then passed to an electron acceptor protein, which passes it along an electron transport chain. As the electron is passed along the transport chain, the electron looses energy, which is used to make ATP from ATP and Pi. The electron is then recycled and enters the photosystem again. The mechanism of ATP production is that when the electron is being passed along the chain, the electron is passed over a proton pump, which uses the negative charge of the electron to pump the proton across the membrane into the thylakoid space. There is a high proton gradient built up insde the thylakoid space. They then move down the gradient, out of an ATPase out of the thylakoid space.

Answered by Samuel H. Biology tutor


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