The energy of photosynthesis comes from light. 1 µm 2 Reactants: 6 CO 2 ADP Products: 12 H 2O C 6H 12O 6 6 H 2O 6 O 2 3 Light H2O Chloroplast Light Reactions NADP+ + P i! 13.5.1.3 Photosystem I Complex. Photosynthesis is a multi-step process that requires sunlight, carbon dioxide (which is low in energy), and water as substrates (Figure 3). The process is known as photosynthesis because, while water and carbon dioxide are the major ingredients required to cook the food, it is light that ignites the stove, and sunlight is the most abundant light that illuminates the planet.. A photosynthetic organism using the energy of photons (photo-), makes its own food (-synthesis). ATP NADPH O 2 Calvin Cycle CO 2 [CH 2O] (sugar) 4 UV Visible light Infrared Micro- waves ... Photosystem I (PS I) Light Primary The question pretty much says everything. Photosynthesis - Photosynthesis - Photosystems I and II: The structural and photochemical properties of the minimum particles capable of performing light reactions I and II have received much study. Molecules called pigments absorb energy from light.The main pigment in photosynthesis is called chlorophyll. Water photolysis and NADP+ reduction - In this phase, the electrons from Photosystem I may be used to reduce NADP+ to NADPH-. The entire process occurs in three significant steps or stages. PS I is a pigment-containing protein complex that can be subdivided into a core complex and antenna complexes. Treatment of lamellar fragments with neutral detergents releases these particles, designated photosystem I and photosystem II, respectively. Step 1: Excitation of Photosystems with Light Energy and Photolysis of Water. What are all the reactants/products for Photosystem I and II? After the process is complete, it releases oxygen and produces glyceraldehyde-3-phosphate (GA3P), simple carbohydrate molecules (which are high in energy) that can subsequently be converted into glucose, sucrose, or any of dozens of other sugar molecules. The principal product of photosynthesis (sugar) is a high-energy molecule, but the reactants (carbon dioxide and water), are low-energy molecules, so the process of photosynthesis needs an energy source to drive it. The function of the light-dependent reaction is to convert light energy into chemical energy within a multi-protein complex called the photosystem, found in the thylakoid membranes. Reaction Center Photosystem I Reaction Center Light Light Materials made and used 6CO 2 + 6H 2 O + sunlight g C 6 H 12 O 6 + 6O 2 Reactants used in Photosystem II: Products made in Photosystem II: Reactants used in Photosystem I: Products made in Photosystem I: The photosystems would not function properly if _____ was not available. The PS I complex functions as a light-driven plastocyanin oxidase and a ferredoxin reductase (Golbeck, 1992; Ikeuchi, 1992). Along with ATP, this molecule plays an important role in light-independent reactions. As this step comes to an end, the now de-energized electron are taken up by photosystem 1 from photosystem II. The light reaction of photosynthesis. Photosystem II is actually used before photosystem I, but they are numbered for the order they were discovered. I'm looking for all for Photosystem I (which is the light reaction), and Photosystem II (the light independent reaction - Calvin Cycle). 1 … The light reaction occurs in two photosystems (units of chlorophyll molecules). Answer Save. The core complex, which contains the reaction center, contains seven polypeptides. Thanks a lot for any answers. Protein complex that can be subdivided into a core complex, which the... But they are numbered for the order they were discovered phase, the from! 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