A photon of light energy travels until it reaches a molecule of chlorophyll. In the light-dependent reactions, light is absorbed and the energy is used to split water molecules. It is recycled back to the light-dependent reactions. Plants cannot use light energy directly to make sugars. Learn about the biology topic The Light-Dependent and Light-Independent Reactions in this free and fun science study guide! The resulting hydrogen ions and electrons are transferred to chemical nicotinamide adenine dinucleotide phosphate (NADP +) to produce reduced nicotinamide adenine dinucleotide phosphate (NADPH) by adding two electrons and a hydrogen ion.At the same … The oxidized chlorophyll is now a very strong oxidizing agent; … These reactions occur in the thylakoids of the chloroplasts. noncyclic electron flow during the light reactions 9 The reactions of the Calvin cycle are not directly dependent on light, but they usually do not occur at night. Light Reactions: Photosystem I & II . Log in for more information. The Calvin cycle uses the reducing powers ATP and NADPH from the light dependent reactions to produce sugars for the plant to use. It's actually occurring simultaneously with the light reactions. The light-dependent reactions of photosynthesis require sunlight. In this stage, the two molecules formed during the light-dependent reaction work together to produce glucose. (2 marks) The scientists' results are shown in the table. The light reaction is a light-dependent process which includes a series of events such as light absorption, hydrolysis, the release of oxygen, formation of ATP and NADPH. Light Reactions: Light-dependent reactions harness energy from the sun to produce chemical bonds, ATP, and NADPH. There are four (4) types of chlorophyll: a, b, c, and d. Others call it the Calvin-Benson cycle to include the name of another scientist inv… The products of the light dependent reactions are used in the light independent reactions is ATP and NADPH. The carbohydrate molecules made will have a backbone of carbon atoms. The second stage of photosynthesis is called the light-independent reaction because sunlight is not necessary for it to occur. Hydrogen atoms from NADPH help to form the glucose, while ATP provides the energy necessary to synthesize it. convert solar energy into chemical energy in the form of NADPH and ATP Both together are the source of the biochemical energy that other plants and animals use to survive. The light-dependent reactions begin in a grouping of pigment molecules and proteins called a photosystem. Duration of light flash / ms Amount of photosynthesis In the Light Dependent reactions ATP and NADPH are produced. It takes place in the thylakoid of […] 6. I don't like using the word dark reaction because it actually occurs while the sun is outside. Most photosynthetic organisms capture visible light, although there are some that use infrared light. After the energy is released, the “empty” energy carriers return to the light-dependent reaction to obtain more energy. The light-dependent reactions begin in a grouping of pigment molecules and proteins called a photosystem. Photosynthesis, the process by which green plants and certain other organisms transform light energy into chemical energy. The first product, and primary reason for the process, is simple sugar. In the light-dependent reactions, energy from sunlight is absorbed by chlorophyll and that energy is converted into stored chemical energy. ... is needed for the end product of glycolysis, pyruvate, to enter the Krebs Cycle. Here is a look at the redox reactions … The Calvin cycle is not totally independent of light since it relies on ATP and NADH, which are products of the light-dependent reactions. Sun, and Carbon Dioxide are taken in. Both the light-dependent reaction and the light- independent reaction take place occurs in chloroplast. 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