Fermentation

Cellular Respiration The respiration that we’ve discussed to this point has all relied on oxygen There are several types of respiration that can occur without oxygen These methods still rely on glycolysis to produce ATP, but create different waste products

What if oxygen is missing? No oxygen available = can’t complete aerobic respiration Cells can undergo: Anaerobic respiration (also known as fermentation) 2 Types: alcohol fermentation lactic acid fermentation no oxygen or no mitochondria necessary (think bacteria) can only make very little ATP large animals cannot survive long term using fermentation yeast bacteria

Anaerobic Respiration lactic acid fermentation bacteria, animals bacteria make yogurt animals feel muscle fatigue glucose  ATP + lactic acid

Lactic acid fermentation Glucose->pyruvic acid -> 2ATP 2 lactic acid GLYCOLYSIS FERMENTATION used to make cheese and yogurt ~ in humans during strenuous exercise not enough oxygen from blood “oxygen debt” ~ lactic acid accumulates in muscle; leads to fatigue and pain Will be converted back to pyruvic acid in liver

Anaerobic Respiration alcohol fermentation yeast make beer, wine, bread glucose  ATP + CO2+ alcohol O2

Alcoholic fermentation glucose -> pyruvic acid-> 2 ethyl alcohol + 2 CO2 2ATP GLYCOLYSIS FERMENTATION used by yeast cells and some bacteria to produce ATP, CO2 and ethyl alcohol