Substrate level phosphorylation forms ATP bc phosphate group transferred from

Substrate level phosphorylation forms atp bc

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Substrate level phosphorylation: forms ATP, b/c phosphate group transferred from ADP. At pyruvate: o If aerobic: goes to Krebs broken into CO 2 o If anaerobic : makes lactate Lactate is made by: glucose + 2 ADP + 2 Pi 2 Lactate + 2 ATP + 2 H2O o In which 2 hydrogens transferred from NADH + H+ to pyruvate, NAD+ regenerates. Then lactate will either go to the blood function in heart and tissues and regenerate as pyruvate or goes to liver to form glucose. If it is going to Krebs: NADH + H+ will transfer to O2 during oxidative phosphorylation regenerating NAD+ and producing H20. The amount of ATP produced by glycolysis (lactate) is much smaller than the ones that go into Krebs and oxidative phosphorylation. Also, carbs such as fructose, galactose can perform glycolysis. Krebs Cycle Involved in nutrient catabolism and ATP production Produces co2, hydrogen and small amounts of ATP. Molecule entering is acetyl CoA comes from pyruvate or breakdown of fatty acids/ AA. Enters the mitochondria from the cytosol. Krebs only does aerobic because O.P. necessary for regeneration of hydrogen free coenzymes. Entering Krebs: Acetyl coA Location: Inner mitochondrial matrix ATP production: 1 GTP, can convert to ATP, only aerobic, (GTP + ADP <--> GDP + ATP) Coenzyme prod: 3 NADH + 2 H+ 2 FADH2 Final Products: 2 CO2 for each acetyl coA
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17 Net Reaction: Acetyl coA + 3 NAD + FAD + GDP + Pi + 2 H2O ---> 2 CO2 + CoA + 3 NADH + 3 H+ + FADH2 + GTP Oxidative Phosphorylation Energy transfer from ATP is derived from energy released when H + + O 2 = H 2 O. From Krebs we have 3 NADH + 2 H + + 2 FADH these hydrogens are pumped in system. Proteins either transfer H + to O 2 or will couple E release to synthesize ATP. These proteins will combine with cytochromes (proteins that have Fe and Cu factors) to transfer 2e- to ETC. These 2e- are transferred to others in the chain to/from cytochromes until they are officially transferred to O Energy is also released during the process cytochromes use this to pump H+ into intermembrane space. o The hydrogen ions flow down concentration gradient across inner mitochondrial membrane through a channel by ATP synthase. ATP synthase takes this energy and synthesizes ATP from ADP + P i . Maximum of 2-3 ATP produced per 1 e- donated. o Chemiosmosis: process in which the inner mitochondrial matrix channel allows for H+ ions to flow back to matrix side. Finally, H + + O 2 = H 2 O Regenerates 2 H + used for glycolysis, Krebs & fatty acids. Regeneration of the H + free form of the coenzyme is aerobic Carbohydrate Metabolism Found in Glycolysis, Krebs and O.P. Amount of E released is 686 kcal/mol and 40% of this energy is transferred to ATP. 2 net ATP phosphorylation in Glycolysis 2 net ATP Krebs 34 ATP Oxidative phosphorylation from generation of ATP.
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