Anaerobic Respiration and Fermentation Chapter 3.3 McGraw-Hill Ryerson Biology 12 (2011)

Anaerobic Respiration Aerobic Respiration: catabolic pathways that require oxygen Anaerobic respiration: catabolic pathways that exclude oxygen

Fermentation Occurs when there is an absence of oxygen NADH that is reduced in glycolysis can’t be reoxidized by electron transport Fermentation provides a different route for NADH to be reoxidized so that glycolysis can continue 2 common pathways are lactate fermentation and alcohol fermentation

Lactate Fermentation Occurs in some single-celled organisms as well as some animal muscle cells that are temporarily without oxygen Pyruvate generated by glycolysis reacts with NADH to rexodize it to NAD+ and ends up as lactate. Lactate is acidic and will cause the surrounding environment to have a lower pH Oxygen required to eliminate lactate in muscle cells is oxygen debt  burning feeling when people run

Alcohol Fermentation Some organisms can function in both aerobic and anaerobic environments facultative anaerobes When in anaerobic environments, they convert pyruvate to ethanol and CO2. Used in baking bread and brewing alcohol

Homework Pg. 137 #1, 3, 4, 5, 7, 9