Respuesta :
Photosynthesis
Explanation:
- Photosynthesis is the process by which photosynthetic organisms transform light energy into chemical energy
- Photosynthesis is an oxidative reductive metabolic pathway in which water is oxidized and carbon dioxide is reduced to carbohydrates
- Light reaction of photosynthesis is concerned with light dependent oxidation of water and synthesis of high energy compounds such as ATP and NADPH
- All proteins and cofactors which involves in light reaction are present in thylakoid membrane hence light reaction of photosynthesis completed in thylakoid membrane
- Transfer of electron and protons in thylakoid membrane is carried out by four protein complexes and two mobile electron carriers
- Oxidation of one water molecule generates two electrons, two protons and one atom of oxygen
- Transfer of one electron from Photosystem II (PSII) to Photosystem I (PSI) requires one photon and transfer of one electron from PSI to NADP+ requires one photon, thus transfer of two electrons from PSII to NADP+ requires four photons
- Flow of two electrons from cytochrome b6f complex drives transportation of four protons from stroma to lumen
- Thus oxidation of one water molecule establish gradient of 6 H+, gradient of 6 H+ drives synthesis of 2 ATP
- Reduction of 1 NADP+ to NADPH requires two electrons, thus oxidation of one eater molecule generates 1 NADPH
