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Photosystem II

Definition

noun

The photosystem that absorbs light for use to drive the oxidation of water and the reduction of plastoquinone, and whose reaction center chlorophyll is P680.


Supplement

Photosystem II is named as such since it is discovered after photosystem I. Their names do not represent the electron flow as it begins in photosystem II I (i.e. when both of them are present in the organism, e.g plants and algae). When photosystem II releases an excited electron, it returns to its ground state by accepting an electron from the oxidation of water molecule whereas photosystem I receives its electron from the electron transport chain, which in turn received an electron from photosystem II.


Abbreviation: PS II

Compare: photosystem I

See also: P680


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I just taught that course (gr 12 photosynthesis): It appears that it is probably extremely unclear. I think it uses 4 photons per photosystem for each H2O broken. But since you need a mix of cyclic and non cyclic light reactions to produce anough ATP and NADPH, and that the cyclic reactions ...

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by canalon
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Is this statement true? Photosystem II is at highe energy level than Photosystem I.

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by chiayen
Sun Jan 15, 2012 4:43 am
 
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by jwalin
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