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This potential is then used to drive ATP synthase and produce ATP from ADP and a phosphate group. Biology textbooks often state that 38 ATP molecules can be made per oxidized glucose molecule during cellular respiration (2 from glycolysis, 2 from the Krebs cycle, and about 34 from the electron transport system). [5]
In plants, ATP is synthesized in the thylakoid membrane of the chloroplast. The process is called photophosphorylation. The "machinery" is similar to that in mitochondria except that light energy is used to pump protons across a membrane to produce a proton-motive force. ATP synthase then ensues exactly as in oxidative phosphorylation. [28]
In anoxygenic photosynthesis, various electron donors are used. Cytochrome b 6 f and ATP synthase work together to produce ATP (photophosphorylation) in two distinct ways. In non-cyclic photophosphorylation, cytochrome b 6 f uses electrons from PSII and energy from PSI [citation needed] to pump protons from the stroma to the lumen. The ...
The hydrogen freed by the splitting of water is used in the creation of two important molecules that participate in energetic processes: reduced nicotinamide adenine dinucleotide phosphate (NADPH) and ATP. In plants, algae, and cyanobacteria, sugars are synthesized by a subsequent sequence of light-independent reactions called the Calvin cycle.
The Calvin cycle uses the chemical energy of ATP and the reducing power of NADPH from the light-dependent reactions to produce sugars for the plant to use. These substrates are used in a series of reduction-oxidation ( redox ) reactions to produce sugars in a step-wise process; there is no direct reaction that converts several molecules of CO 2 ...
The ATP synthase isolated from bovine (Bos taurus) heart mitochondria is, in terms of biochemistry and structure, the best-characterized ATP synthase. Beef heart is used as a source for the enzyme because of the high concentration of mitochondria in cardiac muscle. Their genes have close homology to human ATP synthases. [32] [33] [34]
The scientist Charles Barnes first used the word 'photosynthesis' in 1893. This word is taken from two Greek words, photos, which means light, and synthesis, which in chemistry means making a substance by combining simpler substances. So, in the presence of light, synthesis of food is called 'photosynthesis'.
The generation of ATP by chemiosmosis occurs in mitochondria and chloroplasts, as well as in most bacteria and archaea. For instance, in chloroplasts during photosynthesis, an electron transport chain pumps H + ions (protons) in the stroma (fluid) through the thylakoid membrane to the thylakoid spaces.