Respiration Notes

General

Respiration is the action of enzymes in cells. There are many uses for energy within the body, these include: muscle contraction, cell division, protein synthesis, active transport, growth and the maintenance of a constant body temperature.

Aerobic Respiration

Aerobic respiration is chemical reactions within the cells that use oxygen to break down nutrient molecules to release energy. Word Equation = glucose + oxygen = carbon dioxide + water Symbol Equation = C6H12O6 + 6O2 → 6CO2 + 6H2O The respiration of germinating seeds is affected by temperature. The seeds, like all living things, have an optimum temperature for respiration.

Anaerobic Respiration

Anaerobic respiration is the chemical reactions that occur in cells that break down nutrient molecules to release energy without the use of oxygen. Some organisms can anaerobically respire all of the rime (e.g.tapeworms). Humans can only use anaerobic respiration as a top up-this means that we are obligate aerobes. Lactate is a poison and must be got rid of after anaerobic respiration. This needs oxygen. This is how we build up an O2 debt during exercise. Endurance athletes generally respire aerobically but with lows levels of anaerobic respiration. They must pay off their O2 debt as they go along. Sprinters start aerobically and gradually become anaerobic. Their O2 debt is paid off after the race by breathing deeply. There are 2 types of anaerobic respiration. The first is Alcoholic fermentation.   Glucose = Ethanol + Carbon Dioxide  C6H12O6 → 2 C2H5OH + 2 CO2   Although oxygen is not required for anaerobic respiration the energy released is considerably less (less than 10%).   This is extremely important commercially, it allows baking (the rising of bread), brewing of alcohol and the production of bio-fuels.  The alcohol produced is poisonous to the nervous system.The second type of anaerobic respiration is lactate fermentation.  Glucose = Lactate  C6H12O6 → 2 C3H6O3    This form of anaerobic respiration produces even less energy.