Functions Of Adenosine Triphosphate

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The ATP molecule consists of a sugar molecule (ribose) attached to a base that is composed of carbon and nitrogen atoms (adenine). Attached to the other side of the ribose are three phosphate groups (a phosphate group consists of one phosphorus atom bonded to 4 oxygen atoms). *
ATP Hydrolysis Powers Cellular Work

The phosphate bonds in ATP (adenosine triphosphate) can be broken down by water. When ATP loses a phosphate group in water, this releases energy and creates the products ADP (adenosine diphosphate with two phosphate groups) and an inorganic phosphate. This is an exergonic reaction since energy is released and the reactants (ATP + Water) have a higher energy than the products (ADP+ inorganic phosphate). The hydrolysis (breakdown in
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When oxygen is not present, fermentation of the pyruvic molecule will occur. When oxygen is present acetyl coA enters into the Krebs/ Citric Acid Cycle inside the mitochondrial matrix and is oxidized to CO2 while reducing NAD to NADH. With each turn of the Krebs cycle, a pyruvate is used and one turn of the cycle produces 3NADHs, 1 ATP, 1 FADH2 and CO2. The Krebs cycle also produces water when NADH and FADH2 shuttle electrons down the electron transport chain to oxygen, which is the last electron acceptor; while at the same time protons are being pumped from the mitochondrial matrix to the intermembrane space allowing oxygen to be reduced to water. NADH and FADH2 can be used in the electron transport chain to create ATP by oxidative phosphorylation. During oxidative phosphorylation which takes place in the inner mitochondrial membrane, NADH and FADH2 are used to pump hydrogen ions across the membrane against proton gradients (chemiosmosis process). A protein complex, ATP synthase which is in the membrane and enables protons to pass in different directions, enables ATP production when the protons move down the gradient. It takes ATP to pump a proton against a gradient and since protons have already been pumped against the gradient (done by NADH and FADH2), they can flow back into the mitochondrial matrix producing ATP in the

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