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Biology-Related Homework Help Biochemistry Topic started by: firework6 on Sep 25, 2012



Title: compare cyclic and noncyclic electron flow?
Post by: firework6 on Sep 25, 2012
compare cyclic and noncyclic electron flow?


Title: compare cyclic and noncyclic electron flow?
Post by: juliaroberts on Sep 25, 2012
Noncyclic

Noncyclic photophosphorylation is the process of making ATP and Pi (phosphorylation) using energy derived from light.  It begins with PII and follows these steps:

1.  Photosystem II
2.  Primary Electron Acceptor
3.  ETC
4.  Phosphorylation
5.  PSI
6.  NADPH
7.  Splitting of H20

Cyclic

This occurs when the electrons in the PS I, energized, are recycled.  Energized electrons from PSI join with protein carriers and generate ATP as they pass along the ETC.  In CONTRAST to noncyclic photophosphorylation where the electrons become incorporated into NADPH, electrons in cyclic phto. return to PSI.  here they casn be ebegized again to participate in cyclic or noncyclic electron flow.  Cyclic occurs simultaneously w/ noncyclic photo. to gen. additional ATP.  2 electrons passing through cyclic genberate on avg. about 1 ATP.

Hope I helped

:-)