Biochem- Lecture 4

name the source of electrons, the final electron acceptor and the energy source in oxidative phophorylation
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what is the exact step that needs to happen to initiate electron flow in the electron carrier chainseparation of charge in the reaction centrewhat is plastocyanin analogous tocytochrome cwhere/when are protons pumped in photophosphorylation in plantswhen water is split and in cytochrome b6fif electrons follow the cyclic path in photophosphorylation in platns, what is produced more or less?more ATP is produced and less NADPH is producedwhat are the two soluble proteins in photophosphorylation in plants?plastocyanin and ferredoxinnet equation of electron flow from H2O to NADP+2H2O + 2NADP+ + 8photons -> O2 + 2NADPH + 2H+from one electron to transfer from water to NADP+, how many photons are required?two photons absorbed (one by each photosystem)to form one molecule of O2, how many photons must be absorbed8to form one O2, how many electrons are required?four electrons must be transferred to make one O2, so you require two H2O and two NADP+, and therefore 8 photonswhat is the cofactor of photosystem IIMn4CaO5what is the net rxn initiated by light in photosystem II4P680 + 4H+ + 2PQb + 4photons -> 4P680+ + 2PQbH2after the p680 reaction, we have p680+ which needs to be reduced. How does this happen?from the oxidation of wateris visible light enough to break water?No, we need this x4: 1. light excites p680+ 2. p680+ gives up e 3. Tyr gives e to p680+ 4. Tyr takes e from water splitting complexhow many electrons does photosystem II get from splitting two waters, how many O2 are made?four electrons 1 O2what is the overall reaction of splitting two waters2H2O -> 4e + 4H+ O2splitting two water molecules puts how many protons into the lumen?fourwhat inorganic molecule hosts the water splitting eventMn4CaO5how many protons are put into the lumen by splitting two waters in the water splitting complexfour protonsdescribe the movement of charge when two PQbH2 are madeto make two PQbH2, two water molecules must be split which puts four protons into the lumen. So We have 4H+p. Then, when the two PQbH2 are made, four protons are being taken from the stroma to make the two molecules to this is a reduction of charge on the stroma side.what is cytochrome b6f complex analagous tocomplex IIIwhat a plastoquinone arrives at cytochrome b6f, what happens to its protons and electronsits protons are removed to oxidize the plastoquinone. Its electrons are funneled to plastocyanin, which is a single electron carrier analogous to cytochrome Cdescribe the flow of the electron that goes to plastocyanin from PQH2 what happens to the other electronwhen PQH2 is bound, one of its electrons is passed from FeS to Cyt f and then to the first plastocyanin. So for one PQH2, one plastocyanin is required to take up one electron. the other electron goes down and is passed from Heme bL to Heme Bh to PQ that is bound. When the second PQbH2 arrives at the complex it also gives on electron to this PQ which can then pick up two protons from the stroma and be released as PQH2chlorophyll a and b have ____ in the centre of their heme while cytochrome C and the hemes in the complexes in the ETC have _____ in the centre. Lastly, plastocyanin has _____ in its centre that carriers one electron. does every pigment/protein electron carrier carry one two or both electrons1. Mg 2. Fe 3. Cu each pigment and electron carrier mentioned only carriers on electron at a timewhat is the overall reaction of the PQ cycle in cytochrome b6f complex2H+n + PQH2 + 2PCox -> PQ + 2PCred + 4H+pWhat is the overall movement of charge up its gradient in complex b6f after two plastocyanins grab an electron?in the lumen, -2 is added from the electrons in the plastcyanins and four H+ is added so overall a charge of +2between ferredoxin and plastocyanin, which is a better electron donor (reducing agent)ferredoxinwhat is the electron flow in photosystem I?p700+photons-> p700* -> p700+ e -> chlorophyll -> quinone -> FeS cluster -> ferredoxinhow is p700+ reduced after it donates an electron