What is the Z-scheme in photosynthesis?
What is the Z-scheme in photosynthesis?
The Z-scheme is an energy diagram for electron transfer in the “light reactions” of plant photosynthesis. It applies equally well to photosynthesis by algae and cyanobacteria. The vertical energy scale shows each molecule’s ability to transfer an electron to (i.e., to reduce) the next one from left to right.
What is involved in Z-scheme of photosynthesis 4 points?
In non cyclic photophosphorylation, the whole scheme of transfer of electrons, starting from the PSII, uphill to the acceptor, down the electron transport chain to PSI, excitation of electrons, transfer to another acceptor, and finally down hill to NADP+ causing it to be reduced to NADPH+H+ is called as the Z scheme.
What is the path of electrons in the Z-scheme?
The Z-scheme describes the path of electron transfer from water to NADP+ and depicts each carrier at its midpoint redox potential on a vertical scale with the more reducing (negative Em) components on the top and the more oxidizing (positive Em) on the bottom (Figure 1).
Where does Z-scheme take place?
Light-Dependent Reactions (Z Scheme) (Neațu et al., 2014) Light-dependent reactions happen in the thylakoid membrane of the chloroplasts and occur in the presence of sunlight. The sunlight is converted to chemical energy during these reactions.
Why is it called Z scheme?
– The energy splits the water and extracts the electrons from it, these electrons are formed in the photosystem II move from that system to cytochrome b6 and to Photosystem I. It links the two photosystems in form Z. Hence, the correct answer is option (A).
Which one of the following is involved in Z scheme?
Three major protein complexes are involved in running the “Z” scheme: (1) Photosystem II; (2) Cytochrome bf complex (containing Cytb6; FeS; and Cytf ) and (3) Photosystem I.
Where do the electrons move from the primary acceptor of ps1 in the Z scheme?
In photosystem I, the primary electron acceptor is mostly a Fe-S (iron-sulphur) protein. The reduced primary acceptor transfers the electrons to secondary electron acceptor (mostly P430).
What is the correct sequence of electron transfer in Z scheme of light reaction?
The Z scheme of photophosphorylation follows the following sequence: PSII→Ae−acceptor→BETS→BPSI→Ce−ac. Which of the following options for A, B, C, and D transfer of electrons.
Where does non cyclic electron flow occur?
thylakoid membrane
Being a light reaction, non-cyclic photophosphorylation occurs in the thylakoid membrane.
Why is Z scheme called so?
– For the light-dependent reactions to take place, it has 4 complexes, they are Photosystem I, Photosystem II, and Cytochrome b56, and ATP Synthase, and all these together creates the production of ATP and NADH. It links the two photosystems in form Z. Hence, the correct answer is option (A).
What is called Z scheme?
The “Z‐scheme” describes the oxidation/reduction changes during the light reactions of photosynthesis. Absorption of a photon excites P680 to P680*, which “jumps” to a more actively reducing species.
What is the Z scheme?
The “Z‐scheme” describes the oxidation/reduction changes during the light reactions of photosynthesis. The vertical axis in the figure represents the reduction potential of a particular species—the higher the position of a molecular species, the more negative its reduction potential, and the more easily it donates electrons.
What is the final electron acceptor in photosynthesis?
The final electron acceptor is NADP. In oxygenic photosynthesis, the first electron donor is water, creating oxygen as a waste product. In anoxygenic photosynthesis various electron donors are used.
What is the role of electron transport chain in photosynthesis?
Thus, the electron transport chain is a crucial cellular machinery for its major role in extracting energy via redox reactions in cellular respiration as well as in photosynthesis. The electron transport chain is comprised chiefly of electron donors and acceptors.
What are the electron carriers in photosynthesis?
In photosynthesis, an electron carrier of the light cycles is the nicotinamide adenine dinucleotide phosphate or NADP.