ANAEROBIC RESPIRATION Cellular respiration without oxygen

ANAEROBIC RESPIRATION Occurs when there is not enough oxygen; Pyruvate is degraded without releasing ATP

Pyruvate must be processed to avoid cell death Process is called fermentation The most common fermentations form either alcohol or lactic acid

ALCOHOL FERMENTATION Glucose molecules break down into pyruvic acid Ethanol and Carbon dioxide are produced Using yeast for the fermentation The carbon dioxide may be used to raise Bread Dough or to Carbonate a beverage

LACTATE FERMENTATION Cells turn pyruvate into lactate Occurs in bacteria that eat milk, to form cheeses and yoghurt, or can make food spoil Muscle cells also form lactate during strenuous - type exercise to produce small amounts of energy

ALTERNATE ENERGY SOURCES Carbohydrates are the body’s primary energy source - New simple sugars are used first - Next, stored glycogen from the liver (from past excess carbs) will be processed into glucose.

Alternate forms of energy Lipids When carbohydrate reserves run low, the body will used stored lipid ( from adipose tissue) - A Lipid enters glycolysis - Fatty acids directly enter Krebs cycle - Because fatty acids have more C & H atoms, they produce much more energy than glucose

Alternate forms of energy Protein As a last resort, protein will be used for energy Amino acids are released by cellular digestion of muscle tissues Amino groups are removed The Carbon skeletons are fed into Krebs cycle for about the same amount of energy as sugars.