CLLULAR RESPERATION

Main menu: Anaerobic respiration (fermentation). Aerobic respiration.

Anaerobic respiration (fermentation) It is the ability to respire in the absence of oxygen. Fermentation occurs in the cytoplasm as a series of enzyme controlled stages known as glycolysis. There are two types of fermentation which occurs in the absence of oxygen: 1.Alcoholic fermentation. 2.Lactic acid fermentation. Back

Glycolysis Is a series of enzyme-catalyzed reactions initiated by the activation of a hexose molecule and terminating in the production of two molecules of pyruvate. The energy released during these reactions is stored in the form of ATP. There are two phases of glycolysis: 1.Preparatory phase. 2.Payoff phase.

Preparatory phase In the preparatory phase of glycolysis, two molecules of ATP are consumed in production the of 2 molecules of PGAL from one glucose molecule.

Payoff phase. During this phase a small amount of energy is released, most of the energy available is stored in the end product. Final product is pyruvate.

Postglycolytic reactions. Pyruvate produced at the end of glycolysis can be catabolised under either anaerobic or aerobic conditions.

2 Pyruvate 2 Ethanol 2 Acetyl-CoA 2 Lactate 2CO 2 NADH+H + NAD + NADH+H + O2O2 2CO 2 NADH+H+ NAD + Alcoholic fermentationAerobic respirationLactic acid fermentation

Aerobic respiration. Stages: 1.Glycolysis -occurs in cytoplasm.Glycolysis 2.Krebs cycle -occurs in the matrix of mitochondria.Krebs cycle 3.ETS -occurs on the inner mitochondrial membrane. Back

Krebs cycle Glycolysis ATP Krebs cycle FADH + NADH+H + GTP CO 2 Electron transport chain

Krebs cycle. Enzymes are required. Begins with acetyl Co-A. In one complete cycle 3 NADH+H +,1 FADH 2, 1ATP and 2CO 2 are produced. One molecule glucose completes two circuits.

ETS NAD FP B C A O2O2 12.2kcal 9.9kcal 23.8kcal kcal

ETS Is the last phase of aerobic respiration. Gives much more energy then other phases of aerobic respiration.

Aerobic Respiration in Eukaryotes. Substrate level Phosphorylation ETS ( Oxidative Phosphorylation) ATPFADH 2 NADH+H + Net Gain Glycolysis 2_2x26 ATP Pyruvate - Acetyl CoA __2x36ATP Krebs cycle 22x26x324ATP Total442836ATP