Only chlorophyll a can pass electrons along to the _____. Question 109 1 / 1 point Photophosphorylation differs from oxidative phosphorylation in that Question options: it involves an electron transport chain. To begin photosynthesis, the chlorophyll molecule in photosystem II is excited by sunlight and the energy produced helps to break down a water molecule (H2O) into ½O2 (with electrons removed) and 2H+. Photosystem I (PSI, or plastocyanin-ferredoxin oxidoreductase) is one of two photosystems in the photosynthetic light reactions of algae, plants, and cyanobacteria. Instead, the still-excited electrons are transferred to a photosystem I complex, which boosts their energy level to a higher level using a second solar photon. Water is split in photosystem II to provide electrons for the reactions. • The enzyme ferredoxin/NADP + oxidoreductase (also called NADP. In (a) photosystem II, the electron comes from the splitting of water, which releases oxygen as a waste product. The photosystems are driven by the excited chlorophyll molecules. The granum is stacks of thylakoids. B) It is lost as heat. Electrons are excited in photosystem I. As electrons are passed through the system of electron carriers associated with photosystem II, they lose energy. To begin photosynthesis, the chlorophyll molecule in photosystem II is excited by sunlight and the energy produced helps to break down a water molecule (H2O) into ½O2 (with electrons removed) and 2H+. Chloroplasts are a type of plastid, distinguished by their green color, the result of specialized chlorophyll pigments. Solar radiation excites an electron when it is absorbed by certain chlorophylls that are known as reaction centers. Question options: has P700 at its reaction center. Photosystem II or PS II is the protein complex that absorbs light energy, involving P680, chlorophyll and accessory pigments and transfer electrons from water to plastoquinone and thus works in dissociation of water molecules and produces protons (H+) and O2. The Chloroplast. E) There are two distinct photosystems, linked together by an electron transfer chain. is reduced by NADPH. The removed electrons are excited by the light energy. The one known as Photosystem II contains the same kind of chlorophyll a as Photosystem I but in a different protein environment with an absorption peak at 680 nm. Photosystem II is the first step of photosynthesis, where the chlorophyll molecule uses light energy to take an electron from a water molecule. So what happens in that situation is this electron, after it gets activated or after it gets excited in photosystem I, it's the electron, it eventually ends up-- instead of at NADPH, it ends up at photosystem II. A) It excites electrons of the reaction center of photosystem I. c. combine with ATP. The stroma is the aqueous fluid that holds the different parts together. In order to capture light energy, electrons must become excited and leave a molecule. The photosystem II complex replaced its lost electrons from an external source; however, the two other electrons are not returned to photosystem II as they would in the analogous cyclic pathway. Photosystem I is an integral membrane protein complex that uses light energy to catalyze the transfer of electrons across the thylakoid membrane from plastocyanin to ferredoxin. Treatment of lamellar fragments with neutral detergents releases these particles, designated photosystem I and photosystem II, respectively. The electrons excited by sunlight are replaced by electrons from _____ in photosystem I, and by electrons from _____ in photosystem II. It produces electron-hole in the chlorophyll. Photosystem II
Two photons of light are absorbed causing the production of one reduced plastoquinone
One of the chlorophylls looses two electrons
Process is repeated to reduce another plastoquinone and have a total of four lost electrons
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