12. Photosystem II is the site where water is split into hydrogen ions (H⁺ or protons), an electron and oxygen. Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that can later be released to fuel the organisms' activities. Photosynthesis definition, the complex process by which carbon dioxide, water, and certain inorganic salts are converted into carbohydrates by green plants, algae, and certain bacteria, using energy from the sun and chlorophyll. There are two types of photosystems: Photosystem I (PSI) Photosystem II (PSII) Photophosphorylation is the light-dependent reaction, which occurs in the chloroplasts of the plant cells, specifically, in the thylakoid membranes. The antenna proteins in photosystem 1 absorb another photon, relaying it to the PS1 reaction center called P700. The electrons are energized by chlorophyll molecules within photosystem II and channeled to a reaction center chlorophyll molecule. ... Only photosystem-I is active in cyclic photophosphorylation. An oxidized center, P700 sends out a high-energy electron to nicotin-amide adenine dinucleotide phosphate or NADP+ and reduces it to form NADPH and ATP. Photosystems have been classified into two types: photosystem I (PSI) and photosystem II (PSII) (Figure 5). The growth profile of cyanobacteria presents an S-shape curve, which indicates that a certain amount of time is needed for single cells and groups to develop. Light reaction 1. Therefore, glycolysis was probably the earliest way of making ATP from glucose. Cyanobacteria are a type of prokaryote. The conversion of light energy into chemical energy occurs in a multi-protein known as photosystem. Cyanobacteria and plant chloroplasts have both photosystems, whereas anoxygenic photosynthetic bacteria use only one of the photosystems. The electron transport chain allows electrons to move from photosystem II to photosystem I. Refer to Model 2. a. This is where the plant cell converts light energy into chemical energy. The Krebs cycle and electron transport occur in the mitochondria. 4.8.5.2.1.3 Climate impact. 2) Non – cyclic Photophosphorylation ... Where does photophosphorylation occur? The light-dependent reactions occur on the thylakoid membrane within the chloroplast. The movement of electrons provides the energy necessary to pump additional H ions in to the thylakoid space. The another name for light reaction is Light dependent reaction 2. 1) Cyclic Photophosphorylation. Life first evolved in the absence of oxygen, and glycolysis does not require oxygen. The Calvin Cycle. The H ions will pass through ATP synthase producing ATP. The three main steps in light reaction are Excitation of photosystem by light energy , production of ATP via ele view the full answer The Calvin Cycle reactions occur in the stroma of the chloroplasts. 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