D. KREBS CYCLE

2. occurs in the matrix of the mitochondria 3. only occurs if oxygen is present 1. Krebs cycle allows the cell to get more energy out of the acetyl-CoA product of the oxidation of pyruvate

remember the cell is trying to release NAD + to allow glycolysis to continue produce ATP

COOH O=C CH 2 COOH CH 2 HOC – COOH CH 2 COOH acetyl-CoA CH 3 C=O S-CoA 4. Details H2OH2O CoA-SH hydrase oxaloacetate citrate

COOH CH 2 HOC – COOH CH 2 COOH CH 2 HC – COOH HOCH COOH isomerase citrate isocitrate

COOH CH 2 HC – COOH HOCH COOH CH 2 C=0 COOH NAD + NADH + H + CO 2 dehydrogenase decarboxylase isocitrate alpha-ketoglutarate

COOH CH 2 C=0 COOH CH 2 C=O S – CoA NAD + NADH + H + CO 2 CoASH dehydrogenase decarboxylase alpha-ketoglutarate succinyl-CoA

COOH CH 2 C=O S – CoA COOH CH 2 COOH CoASH GTP GDP + Pi ADP ATP phosphorylase H2OH2O hydrase succinyl-CoA succinate

COOH CH 2 COOH CH ll HC COOH FAD + H2H2 dehydrogenase FAD succinate fumarate

COOH CH ll HC COOH HOCH CH 2 COOH H2OH2O hydrase fumarate malate

COOH HOCH CH 2 COOH O=C CH 2 COOH NAD + NADH + H + dehydrogenase malate oxaloacetate

START AGAIN COOH O=C CH 2 COOH CH 2 HOC – COOH CH 2 COOH acetyl-CoA CH 3 C=O S-CoA Oxaloacetate citric acid so this is sometimes called the citric acid cycle

5. EQUATION: acetyl-CoA +3 NAD + +FAD + +H 2 0 +ADP + Pi 2 CO 2 +3 [NADH + H + ] +FADH 2 +ATPCoASH +

E. SUMMARY – so far for HIGH ENERGY PRODUCTS where glucoseglycolysis cytoplasm 2 ATP oxidation of pyruvate matrix of mitochondria 2 [NADH + H + ] 4 ATP

oxidation of pyruvate Kreb’s cycle 2 [NADH + H + ] 2 ATP 6 [NADH + H + ] 2 FADH 2 matrix of mitochondria where

remember the cell is trying to release NAD + to allow glycolysis to continue produce ATP Krebs made no NAD +, it used 6 Krebs made only 2 more ATP