How many ATP are produced in cyclic Photophosphorylation?

Therefore, H+/ATP = 4.67, e-/NADPH + H+ = 2, Total ATP release in both photphosphorylation during evolution of an oxygen molecule = 3, total NADPH + H+ during evolution of an oxygen molecule at PS-II = 2 Therefore, ATP/NADPH formation from cyclic photophosrylation at P680 = 7/9 (instead of the expected 3/2) and ATP …

Does cyclic Photophosphorylation generate ATP?

The ATP and NADPH from the light-dependent reactions are used to make sugars in the next stage of photosynthesis, the Calvin cycle. In another form of the light reactions, called cyclic photophosphorylation, electrons follow a different, circular path and only ATP (no NADPH) is produced.

How ATP is formed in cyclic Photophosphorylation?

Cyclic photophosphorylation involves only Photosystem I and generates ATP but not NADPH. As the accumulating protons in the thylakoid interior space pass back across the thylakoid membrane to the stroma through ATP synthetase complexes, this energy is used to generate ATP from ADP and Pi (Figure 18.7B.

Where is ATP produced in cyclic Photophosphorylation?

thylakoid membranes
Cyclic photophosphorylation Light-dependent electron transport occurs in the thylakoid membranes, where electrons follow a cyclic pathway, returning to the photosystem I reaction center. The energy of this electron transport results in a H+ gradient formation, the energy source for ATP synthesis.

Why do plants use 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.

What is the advantage of cyclic Photophosphorylation?

The cyclic photophosphorylation also results in the formation of ATP molecules just like in non – cyclic photo phosphorylation. As the electrons move downhill in the electron transport chain, they lose potential energy and ATP molecules are formed in the same way as in mitochondria during respiration.

What is the purpose of cyclic Photophosphorylation?

Cyclic photophosphorylation This transport chain produces a proton-motive force, pumping H+ ions across the membrane and producing a concentration gradient that can be used to power ATP synthase during chemiosmosis.

What is the advantage of cyclic photophosphorylation?

Why do bacteria use cyclic photophosphorylation to generate ATP?

In the presence of organic compounds, the purple bacteria often exist as photoheterotrophs, utilizing cyclic photophosphorylation to generate ATP and getting their organic compounds from the environment. This eliminates the need for using reverse electron flow, an energetically unfavorable process, as well as the need for external electron donors.

What is the process of cyclic photophosphorylation?

Cyclic Photophosphorylation. The photophosphorylation process which results in the movement of the electrons in a cyclic manner for synthesizing ATP molecules is called cyclic photophosphorylation. In this process, plant cells just accomplish the ADP to ATP for immediate energy for the cells.

How is NADP + involved in non cyclic photophosphorylation?

On the other hand, non-cyclic photophosphorylation, NADP+ does not take the electrons; they instead sent back to cytochrome b6f complex. In bacterial photosynthesis, a single photosystem is needed and therefore is involved in cyclic photophosphorylation.

How are green phototrophic bacteria used in phototrophy?

Green phototrophic bacteria also engage in anoxygenic phototrophy, utilizing a single photosystem with bacteriochlorophyll for cyclic photophosphorylation in the production of ATP. However, they also use this same photosystem for generation of reducing power, by periodically drawing off electrons to NAD+.