Why is it called photophosphorylation

Cell Introduction 2. Cell Structure 3. Membrane Structure 4. Membrane Transport 5. Origin of Cells 6. Cell Division 2: Molecular Biology 1. Metabolic Molecules 2. Water 3. Protein 5. Enzymes 6. Cell Respiration 9. Photosynthesis 3: Genetics 1. Genes 2. Chromosomes 3. Meiosis 4. Inheritance 5. Genetic Modification 4: Ecology 1. Energy Flow 3. This splitting of water is responsible for the release of O 2 into the air.

Each photoexcited electron energized by light passes from the primary electron acceptor in photosystem II to photosystem I via an electron transport chain. This electron transport chain is very similar to the one in cellular respiration; however, the carrier proteins in the chloroplast ETC are different from those in the mitochondrial ETC. The production of ATP in the chloroplast is called photophosphorylation because the energy harnessed in the process originally came from light.

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. Within the membranes, chlorophyll molecules absorb photons.

The absorbed photons energize electrons from chlorophyll, causing them to jump into an electron transport chain. As the electrons pass from one component of the chain to the next, they release their excess energy. The high concentration of protons inside the thylakoids represents potential energy that the cell can tap to make ATP. The cell makes this ATP when the protons flow back down their concentration gradient, through the ATP synthase complex.