Photosystem I or PS 1 contains chlorophyll A-670, chlorophyll A-680, chlorophyll A-695, chlorophyll A-700, chlorophyll B, and carotenoids. Chlorophyll a and chlorophyll b are approximately equal. When light hits this photosystem, the electron is bounced to a higher energy level. The pigments in the photosystem2 absorb shorter wavelengths of light which is 680 nm (P680). Photosystem II is the second photosystem to develop in most higher autotrophs. 3. Chlorophyll a content is more than twice that of chlorophyll b. a. light-dependent reaction b. carbon fixation reaction c. CAM pathway Chlorophyll is the pigment involved in capturing light energy. Its photo Centre is P 680. Photosystem I and II don't align with the route electrons take through the transport chain because they weren't discovered in that order. Photosystem II is present on the thylakoid membranes inside chloroplasts, the site of photosynthesis in green plants. The antenna system serves to capture light energy and transfer it to the core efficiently. But it was too late, the name stuck. It is not connected with photolysis of water. The light reaction occurs in two photosystems (units of chlorophyll molecules). Galka P, Santabarbara S, Thi THK et al (2012) Functional analyses of the plant photosystem I-light-harvesting complex II supercomplex reveal that light-harvesting complex II loosely bound to photosystem II is a very efficient antenna for photosystem I in state II. The red alga Cyanidioschyzon merolae is a primitive organism, which is capable of performing photosynthesis in extreme acidic and hot environments. But if we see their function, photosystem II comes before photosystem I. Photosystem II is located in at the inner surface of grana of thylakoid. 2. Photosystem II is one of a system of photosystems involved in photosynthesis. Photosystem I absorbs light with wavelengths shorter than 700 nm, whereas photosystem II absorbs light with wavelengths shorter than 680 nm. B. the light reactions only. It works together with Photosystem I to absorb enough energy to the separate the oxygen of a water molecule from its e-. Photosystem II is involved in the light driven reactions, called electron transport chain. Core Composition in the PSI is made up of two subunits which are psaA and psaB, and PS II is made up of two subunits made up of D1 and D2. Photosystem II was discovered later. The key difference between photosystem 1 and photosystem 2 is that the photosystem 1 has a reaction centre composing of chlorophyll a molecule of P700 that absorbs light at a wavelength of 700 nm. In photosystem II, the electron comes from the splitting of water, which releases oxygen as a waste product. The structural and photochemical properties of the minimum particles capable of performing light reactions I and II have received much study. Privacy. Chlorophyll a and chlorophyll b are approximately equal. This system is involved in both cyclic photophosphorylation. Quizlet flashcards, activities and games help you improve your grades. It receives electrons from photosystem II. 7. Reaction center chlorophylls P700 and P680. Photosystem I was discovered first. It works together with Photosystem I to absorb enough energy to the separate the oxygen of a water molecule from its e-. PS 1 contains chlorophyll B, chlorophyll A-670, Chlorophyll A-680, chlorophyll A-695, chlorophyll A-700 and carotenoids. 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