Why do plants need 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.

Why is non-cyclic photophosphorylation important?

This process of ATP production is called non-cyclic photophosphorylation. The ATP generated in this process will provide the energy for the synthesis of glucose during the Calvin cycle (light independent reactions). NADPH is the reducing agent needed for the synthesis of glucose in the Calvin cycle.

Does not happen in cyclic photophosphorylation?

NADPH formation does not take place in cyclic photophosphorylation. In this pathway, only a single molecule of ATP is synthesised.

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.

Why would an organism perform cyclic phosphorylation instead of Noncyclic phosphorylation?

Noncyclic photophosphorylation is used in oxygenic photosynthesis when there is a need for both ATP and NADPH production. If a cell’s needs for ATP outweigh its needs for NADPH, then it may carry out cyclic photophosphorylation instead, producing only ATP.

How does cyclic differ from Noncyclic photophosphorylation?

In the cyclic photophosphorylation, only ATP is produced, whereas, in the non-cyclic photophosphorylation both NADPH and ATP are produced. In cyclic photophosphorylation, the electrons get expelled by photosystem I and they return to the system.

Why is ATP so important for the plant?

ATP is an important source of energy for biological processes. Energy is transferred from molecules such as glucose, to an intermediate energy source, ATP. In photosynthesis energy is transferred to ATP in the light-dependent stage and the ATP is utilised during synthesis in the light-independent stage.

How does cyclic differ from Noncyclic Photophosphorylation?

Why do plants use cyclic electron flow?

In higher plants, the generation of proton gradient across the thylakoid membrane (ΔpH) through cyclic electron flow (CEF) has mainly two functions: (1) to generate ATP and balance the ATP/NADPH energy budget, and (2) to protect photosystems I and II against photoinhibition.

Where does photophosphorylation occur in plants?

Photophosphorylation is the light-dependent reaction, which occurs in the chloroplasts of the plant cells, specifically, in the thylakoid membranes. What is cyclic photophosphorylation?

Why is cyclic photophosphorylation a wasteful reaction?

Cyclic photophosphorylation is a highly wasteful reaction because one of the two photosystems absorbs light energy but does nothing. However, the reaction raises the ratio of produced ATP to produced NADPH and is obviously needed. What’s the difference between non-cyclic and cyclic photophosphorylation in relation to PSI and PSII?

What is cyclic photophosphorylation in prokaryotes?

Cyclic Photophosphorylation. In prokaryotes, the process of photosynthesis is used for the production of energy and not for the formation of biological molecules. Cyclic Photophosphorylation is the process, in which systems (like prokaryotes), just accomplishes the ADP to ATP for immediate energy for the cells. This type…

How does cyclic photophosphorylation increase the amount of ATP produced?

When there is high demand for ATP the proportion of cyclic photophosphorylation will increase to provide ATP (yes, it is true that they (probably) provide the same ‘amount’ of ATP per cycle, but the rate of ATP production with cyclic photophosphorylation is probably greater since it is an overall much shorter process.) 4.