Answer: 1] sunlight strikes the chloroplast of a green plant. 2] the light
harvesting antennae (photosystem II) absorbs the energy of sunlight which
excites an electron in the chlorophyll a molecule. the chlorophyl a
(photosystem II) absorbs light with a wavlength of 680nm best (chlorophyll
a P680). 3] an electron will be emmitted from chlorophyll a(P680) and
travel to the primary electron acceptor. 4] this creates a "electron hole"
5] sunlight is used to split a molecule of water into hydrogen ions,
electrons and oxygen (photolysis). 6] the electrons are used to replace the
electrons lost in the chlorophyl a (P680) molecule. 7] the electron hole is
filled so steps1,2,3 can be done again 8](e-) ->primary electron acceptor
->plastoquinone ->cytochrome complex (generates ATPs) ->plastocyanin 9] the
electron reaches the chlorophyl a(P700) of photosystem I
photosystem II (non cyclic electron flow)
More Photosystem II (non Cyclic Electron Flow) images
Cyclic vs. Non-cyclic Electron Flow . Under certain conditions the photoexcited electrons take an alternative path called cyclic electron flow which uses photosystem I (P700) but not photosystem II (P680). This process produces no NADPH and no O 2 but it does make ATP. This is called cyclic photophosphorylation. The chloroplast shifts to this process when the ATP supply drops and the level of NADPH rises.
Non-Cyclic Electron Flow Non-cyclic electron flow also involves PS1 and occurs on the thylakoid membrane but it begins with another integral membrane protein complex called Photosystem II. The first step is similar in both cyclic and non-cyclic electron flow. The reaction center in PS2 holds an electron that becomes excited.
Photosystem II - cyclic electron flow powers exceptional photoprotection and record growth in the microalga Chlorella ohadii. Ananyev G(1) Gates C(1) Kaplan A(2) Dismukes GC(3). Author information: (1)The Waksman Institute of Microbiology Rutgers University Piscataway NJ 08854 United States; Department of Chemistry and Chemical Biology ...
The photophosphorylation process which results in the movement of the electrons in a non-cyclic manner for synthesizing ATP molecules using the energy from excited electrons provided by photosystem II is called non-cyclic photophosphorylation.
2-Non-cyclic Photophosphorylation. The photophosphorylation process which results in the movement of the electrons in a non-cyclic manner for synthesizing ATP molecules using th...