What you should know from today’s lecture The importance of glycolysis, fermentation, and respiration (Krebs cycle) in biology The site of glycolysis, fermentation, and respiration in prokaryotes and eukaryotes Overall chemical reactions of glycolysis, fermentation, and respiration Mitochondrion structure Poisons affecting respiration

The importance of glucose metabolism The most primitive and universal method for capturing and converting chemical energy Performed by all organisms, auto- and heterotrophs Fermentation pathways are ancient but inefficient Aerobic respiration is efficient but requires oxygen (from photosynthesis)

Energy release from glucose Glucose (6 C) Lactate (3 C) Glycolysis 2 Pyruvate (3 C) 2 ATP 6 CO H 2 O Ethanol (2 C) + CO 2 Lactate fermentation Alcoholic fermentation Aerobic respiration ATP 6O 2

Glycolysis: overview All cells can perform glycolysis -- universal source of energy (ATP) and carbon skeleton Glycolysis takes place in the cytoplasm What is NAD+?

Fig. 8.4b, p. 135 Glycolysis I

Fig. 8.4c, p. 135 Glycolysis II

Aerobic respiration: overview Aerobic respiration takes place in the cytoplasm and membrane of prokaryotes, and in the mitochondria of eukaryotes

Fig. 8.6, p. 137 Aerobic respiration

Fig. 8.5a, p. 136 (see next slide) Mitochondrion

Fig. 8.5b, p. 136 Chemiosmotic ATP formation

ATP yield from aerobic respiration

Fermentation Lactate fermentation Alcoholic fermentation Site of lactate fermentation: Examples of lactate fermentation: Site of alcoholic fermentation: Examples of alcoholic fermentation: Lactate dehydrogenase (LDH)

Metabolic poisons

Fig. 8.12, p. 143 Metabolism