What are the electron carriers used in photosynthesis called ..
LabBench Activity Plant Pigments and Photosynthesis
The cartoon at bottom depicts a "cut-away" chloroplast view. The outerenvelope, as you know, is permeable to metabolites and even small proteins. We focused onthe transporters of the inner envelope of the chloroplast, which is continuous with theextensive membranous system of the interior, a point that we will return to later. As wediscussed before, the aqueous interior of the chloroplast is the stroma, the site of theRPPP. Photosynthetic electron transport occurs in (or across) the thylakoid membranes ofthe interior. These membranes exist as sheets (like the ER), and as the cartoon shows,they enclose a lumen ("cavity"). By way of review, then, there are three aqueousspaces: (1) the space between the envelope membranes, (2) the stroma, and (3) thethylakoid lumen. As you will see, the thylakoid membranes not only harvest light, but theyseparate two regions in which the electrochemical potentials of H+ differconsiderably as a consequence of electron transport. At this point, please note that thereis considerable organization in the interior membranes: Some sheets traverse the stroma,("stromal lamella") and are not associated with others. Some of the membranesform stacks; stacks of thylakoids are called grana (sing. granumfromthe grainy appearance in the light microscope).
IB Biology Notes - 8.2 Photosynthesis
As mentioned in the introduction, we will discuss four major components of thephotosynthetic electron transport system. These components are shown as the differentsymbols keyed in the upper right hand corner of the diagram. Two techniques(freeze-fracture and two-phase polymer systems that enable investigators to isolatephysically very similar biological structures [such as the different chloroplast membranesor the cis vs. trans faces of Golgi] have shown that the four components are not equallydistributed through out the membranes. To facilitate our later discussions, I would ask you to commit to memory now: (1) The ATPase and PSI are localizedexclusively in the non-appressed regions. (2) PSII is localized mostly in the appressedregions. (3) The b-f complex is abundant in both the appressed and non-appressed regions.