AIM 35: How can some parts of cellular respiration proceed without oxygen? Honors Biology

Glycolysis Breaks glucose down into two molecules of pyruvate Breaks glucose down into two molecules of pyruvate Occurs in the cytoplasm Occurs in the cytoplasm Initial investment of 2 ATP Initial investment of 2 ATP Net gain of 2 ATP and 2 NADH Net gain of 2 ATP and 2 NADH ATP is made by substrate level phosphorylation— when an enzyme transfers a phosphate group to ADP ATP is made by substrate level phosphorylation— when an enzyme transfers a phosphate group to ADP

Kreb’s Cycle/Citric Acid Cycle The products of glycolysis (2 pyruvates) are used in the next step--citric acid cycle The products of glycolysis (2 pyruvates) are used in the next step--citric acid cycle Occurs in the mitochondrial matrix (fluid inside the inner membrane) Occurs in the mitochondrial matrix (fluid inside the inner membrane) This cycle completely oxidizes (removes electrons from) the pyruvate molecules from glycolysis This cycle completely oxidizes (removes electrons from) the pyruvate molecules from glycolysis Makes 8 NADH and 2 FADH 2 Makes 8 NADH and 2 FADH 2 Electron carriers (and H+) Electron carriers (and H+) Yields 2 ATP Yields 2 ATP

Neither glycolysis nor the citric acid cycle require oxygen Neither glycolysis nor the citric acid cycle require oxygen Glycolysis makes compounds that the citric acid cycle will use Glycolysis makes compounds that the citric acid cycle will use The citric acid cycle makes compounds that the electron transport chain will use The citric acid cycle makes compounds that the electron transport chain will use In summation: In summation: Glycolysis and the Krebs Cycle yield a total of Glycolysis and the Krebs Cycle yield a total of 4 ATP, 10 NADH and 4 ATP, 10 NADH and 2 FADH 2 2 FADH 2