AIM 35: How can some parts AIM 35: How can some parts of cellular respiration of cellular respiration

proceed without oxygen?proceed without oxygen?

Honors BiologyHonors Biology

GlycolysisGlycolysis Breaks glucose down into Breaks glucose down into

two molecules of pyruvatetwo molecules of pyruvate Occurs in the cytoplasmOccurs in the cytoplasm

Initial investment of 2 ATPInitial investment of 2 ATP

Net gain of Net gain of 2 ATP2 ATP and and 2 2 NADHNADH ATP is made by ATP is made by substrate substrate

level phosphorylation—level phosphorylation—when an enzyme transfers when an enzyme transfers a phosphate group to ADPa phosphate group to ADP

Kreb’s Cycle/Citric Acid Kreb’s Cycle/Citric Acid CycleCycle

The products of glycolysis (2 The products of glycolysis (2 pyruvates) are used in the next pyruvates) are used in the next step--citric acid cyclestep--citric acid cycle Occurs in the mitochondrial matrix Occurs in the mitochondrial matrix

(fluid inside the inner membrane)(fluid inside the inner membrane)

This cycle completely oxidizes This cycle completely oxidizes (removes electrons from) the (removes electrons from) the pyruvate molecules from glycolysispyruvate molecules from glycolysis

Makes Makes 8 NADH and 2 FADH8 NADH and 2 FADH22 Electron carriers (and H+)Electron carriers (and H+)

Yields Yields 2 ATP2 ATP

Neither glycolysis nor Neither glycolysis nor the citric acid cycle the citric acid cycle require oxygenrequire oxygen

Glycolysis makes Glycolysis makes compounds that the compounds that the citric acid cycle will use citric acid cycle will use

The citric acid cycle The citric acid cycle makes compounds that makes compounds that the electron transport the electron transport chain will usechain will use

In summation:In summation: Glycolysis and the Glycolysis and the

Krebs Cycle yield a Krebs Cycle yield a total of total of

4 ATP, 10 NADH and 4 ATP, 10 NADH and 2 FADH2 FADH22