Three Metabolic Pathways

Pathways of Cell Respiration 2 234

2 ATP Glycolysis Summary GLUCOSE PYRUVATE PYRUVATE NADH H + NADH To ETC Ready to use

2 NAD + 2 NADH Fermentation Some orgs lack the O 2 or tools necessary for KC or ETC Some orgs lack the O 2 or tools necessary for KC or ETC Leads to buildup of useless pyruvate and NADH Leads to buildup of useless pyruvate and NADH Fermentation Fermentation Elimination of pyruvate Elimination of pyruvate Recycling of NAD + Recycling of NAD + PYR PYRGlucoseGlucose 2 ATP Fermentation Aerobic Cell Resp

Alcohol Fermentation Diffuses out of cell Diffuses out of cell Available for glycolysis

Alcohol Fermentation Uses

Lactic Acid Fermentation Diffuses out of cell Available for glycolysis

PYRUVATE Pyruvate Oxidation (for each of 2 pyruvates) CO 2 NADH ACETYL CoA CoA To Cycle Diffuses Away (Waste) To ETC

Citric Acid Cycle Subsequent rxns break down the citrate into another oxaloacetate. Acetyl CoA (2C) Oxaloacetate (4C) Citrate (6C)

NADH FADH 2 NADH Citric Acid Cycle 4C OXALOACETATE 2C ACETYL CoA 6C CITRATE 5C NADH 4C ATP

Glycolysis Before Before Glucose Glucose 2 NAD 2 NAD 2 ADP + P 2 ADP + P After After 2 Pyruvate 2 Pyruvate 2 NADH 2 NADH 2 ATP 2 ATP Matrix (Krebs) Matrix (ETC) Where needed

Krebs Cycle (including lead-up steps) Before Before 2 Pyruvate 2 Pyruvate 8 NAD 8 NAD 2 FAD 2 FAD 2 ADP + P 2 ADP + P After After 6 CO 2 6 CO 2 8 NADH 8 NADH 2 FADH 2 2 FADH 2 2 ATP 2 ATP Diffuse away IMM (ETC) Where needed

ETC  Chemiosmosis

Alternate Catabolism Deamination

Regulation Phosphofructokinase Phosphofructokinase Catalyzes one step of glycolysis Catalyzes one step of glycolysis Inhibited by Inhibited by ATP and Citrate ATP and Citrate Stimulated by Stimulated by ADP and AMP ADP and AMP AA production AA production Inhibited by large amounts of AA’s Inhibited by large amounts of AA’s

Cell Respiration Review Which part of CR? 1.CO 2 is given off 2.Most water is formed 3.Oxaloacetate 4.Pyruvate production 5.ATP Production

Cell Respiration Review Put the following molecules in order of increasing electronegativity: Glucose FADH 2 O 2 NADH GlucoseNADH FADH 2 O 2

Cell Respiration Review What is the primary product of cellular respiration? Why would an organism carry out fermentation when aerobic cellular respiration is so much more profitable? What is the energy source for the ETC? What’s the immediate result of an ETC? What can a cell do with that?