The final electron acceptor is NADP. … In non-cyclic photophosphorylation, cytochrome b6f uses the energy of electrons from PSII to pump protons from the lumen to the stroma. The proton gradient across the thylakoid membrane creates a proton-motive force, used by ATP synthase to form ATP.
How are electrons replaced in non-cyclic photophosphorylation?
Noncyclic photophosphorylation involves both Photosystem I and Photosystem II and produces ATP and NADPH. … These electrons continuously replace the electrons being lost by the P680 chlorophyll a molecules in the reaction centers of the Photosystem II antenna complexes (Figure 18.7B. 2).
What is the difference between cyclic photophosphorylation and Noncyclic photophosphorylation?
Difference Between Cyclic and Noncyclic Photophosphorylation
In the cyclic photophosphorylation, P700 is known to be the active reaction centre. In the non-cyclic photophosphorylation, P680 is known to be the active reaction centre. Electrons tend to pass in a cyclic manner.
What is the advantage of cyclic photophosphorylation?
When the plant has enough reducing agent (NADPH), there is no need for the production of more NADPH that involve both photosystems (I and II). In cyclic photophosphorylation only photosystem I is active. So, The cyclic one is needed at this time because it can generate ATP with less cost.
Is NADP an electron acceptor?
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 water in non-cyclic photophosphorylation?
What is the role of water in noncyclic photophosphorylation? It directly generates ATP.
Which one is correct the final acceptor of electrons?
Correct answer:
Oxygen is the final electron acceptor in the electron transport chain, showing the need for aerobic conditions to undergo such a process.
Which is stimulus for cyclic phosphorylation?
Cyclic photophosphorylation involves the use of photosystem-I. When light is absorbed by this photosystem, the excited electron enters the electron transport chain to produce ATP.
What is the difference between linear and cyclic electron flow?
In linear electron flow (unbroken arrows) energy from absorbed photons is used to oxidise water on the luminal face of photosystem II (PS II). … In cyclic electron flow, energy from absorbed photons causes the oxidation of the reaction centre (P700) in PS I.
Which of the following is produced in Noncyclic photophosphorylation but not cyclic photophosphorylation?
Oxygen is produced in noncyclic photophosphorylation but not in cyclic photophosphorylation. Cyclic photophosphorylation involves a single photosystem.
Where does non-cyclic photophosphorylation takes place?
Complete answer: Non-cyclic phosphorylation takes place in the granal thylakoid region of chloroplast. Two photosystems i.e. Photosystem-I and Photosystem-II is involved in the process of non-cyclic phosphorylation.
What do you mean by non-cyclic photophosphorylation?
non-cyclic photophosphorylation The light-requiring part of photosynthesis in higher plants, in which an electron donor is required, and oxygen is produced as a waste product. It consists of two photoreactions, resulting in the synthesis of ATP and NADPH 2.
Why does cyclic photophosphorylation occur?
This is called cyclic photophosphorylation. The chloroplast shifts to this process when the ATP supply drops and the level of NADPH rises. Often the amount of ATP needed to drive the Calvin cycle exceeds what is produced in non-cyclic photophosphorylation.
What is the role of water in non-cyclic electron flow?
Water is oxidized as a result of the light reaction of photosystem II. … Another light reaction at photosystem I activates electrons for transfer to ferredoxin, and finally to NADP+ . The overall equation for non-cyclic electron transport. Water is oxidized to oxygen, releasing protons.
What is the role of water in cyclic Photophosphorylation?
What is the role of water in cyclic photophosphorylation? It provides electrons and protons. Where do the electrons from photosystem I ultimately go after they are passed through the electron transport proteins? They return to photosystem I.
Why does a plant use both cyclic and noncyclic pathways?
Noncyclic electron transport produces ATP AND NADPH. Cyclic electron transport only produced ATP. A plant needs both processes to make enough ATP necessary for the Calvin Cycle.
Is NADP+ a hydrogen acceptor?
Hydrogen dehydrogenase (NADP+)
This enzyme belongs to the family of oxidoreductases, specifically those acting on hydrogen as donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is hydrogen:NADP+ oxidoreductase.
Is fad a hydrogen acceptor?
dinucleotide (FAD), yielding NADH and FADH2. It is the subsequent oxidation of these hydrogen acceptors that leads eventually to the production of ATP.
How many electrons can ferredoxin carry?
When NADP+ and a suitable enzyme are present, two ferredoxin molecules, carrying one electron each, transfer two electrons to NADP+, which picks up a proton (i.e., a hydrogen ion) and becomes NADPH.
Why is the cyclic pathway so important?
With the cyclic pathway, plants can save some time and energy. Since photosystem I is accepting electrons that are returned to it, it is not accepting electrons from the previous electron transport chain. Therefore, the first electron transport chain will be backed up, which means that photolysis will not occur.
What is the difference between cyclic and noncyclic electron transport?
Cyclic photo-phosphorylation in photosynthesis light dependent reaction leads to the formation of ATP and NADPH, and the electrons go from water to PSII to PSI and eventually to NADPH. In non-cyclic photo-phosphorylation only some ATP is produced and the electrons go from PSII to PSI and back again.
Which step of non-cyclic Photophosphorylation is blocked by Dcmu?
DCMU is a very specific and sensitive inhibitor of photosynthesis. It blocks the QB plastoquinone binding site of photosystem II, disallowing the electron flow from photosystem II to plastoquinone.