What is the Difference Between Cyclic and Noncyclic Photophosphorylation?
🆚 Go to Comparative Table 🆚Cyclic and noncyclic photophosphorylation are two processes used for synthesizing energy-rich ATP molecules in the presence of light energy during photosynthesis. The main differences between them are:
- Involvement of Photosystems: Cyclic photophosphorylation involves only Photosystem I (PSI), while noncyclic photophosphorylation involves both Photosystem I (PSI) and Photosystem II (PSII).
- Electron Flow: In cyclic photophosphorylation, electrons from PSI are cycled back to PSI via an electron transport chain, generating a proton gradient used to produce ATP by ATP synthase. In noncyclic photophosphorylation, electrons are transferred from PSII to PSI via an electron transport chain, and electrons from PSI are used to reduce NADP+ to NADPH.
- Product Formation: Cyclic photophosphorylation only produces ATP, while noncyclic photophosphorylation produces both ATP and NADPH.
- Oxygen Production: Noncyclic photophosphorylation involves the photolysis of water, which leads to the release of oxygen. In contrast, cyclic photophosphorylation does not involve water photolysis and does not release oxygen.
- Occurrence: Cyclic photophosphorylation is predominantly found in photosynthetic bacteria and isolated chloroplasts, while noncyclic photophosphorylation occurs in algae, cyanobacteria, plants, and other oxygenic phototrophs.
On this pageWhat is the Difference Between Cyclic and Noncyclic Photophosphorylation? Comparative Table: Cyclic vs Noncyclic Photophosphorylation
Comparative Table: Cyclic vs Noncyclic Photophosphorylation
Here is a table summarizing the differences between cyclic and noncyclic photophosphorylation:
Feature | Cyclic Photophosphorylation | Noncyclic Photophosphorylation |
---|---|---|
ATP Production | Produces ATP molecules | Produces both NADPH and ATP molecules |
Water Requirement | Water is not required | Photolysis of water is present |
NADPH Production | NADPH is not synthesized | NADPH is synthesized |
Photosystem Involvement | Only Photosystem I is involved | Both Photosystem I and II are involved |
Active Reaction Center | P700 is the active reaction center | P680 is the active reaction center |
Cyclic photophosphorylation occurs in photosystem I, does not require water, and only produces ATP. In contrast, noncyclic photophosphorylation involves both photosystems I and II, requires water, and produces both NADPH and ATP molecules. The electrons lost by P680 in noncyclic photophosphorylation do not return to the system, whereas in cyclic photophosphorylation, the electrons expelled by photosystem I return to the system.
Read more:
- Oxidative phosphorylation vs Photophosphorylation
- Phosphorylation vs Dephosphorylation
- Substrate Level Phosphorylation vs Oxidative Phosphorylation
- ATP vs NADPH
- Cyclic AMP vs AMP
- Light Reaction vs Calvin Cycle
- Cathodoluminescence vs Photoluminescence
- Acyclic vs Cyclic Organic Compounds
- Photoluminescence vs Fluorescence
- Cytosolic vs Chloroplastic Glycolysis
- Phosphoryl Group vs Phosphate Group
- Photocatalysis vs Electrocatalysis
- Carbon Cycle vs Phosphorus Cycle
- Cyclins vs Cyclin Dependent Kinases
- Phosphorylase vs Phosphatase
- Fluorescence vs Phosphorescence
- Photosystem 1 vs Photosystem 2
- Cyclic vs Reversible Process
- Cytochrome vs Phytochrome