High School Biology/Anaerobic Respiration

Anearobic Respiration


Anearobic respiration is a catabolic (breaking down) reaction that occurs in both plant and animal cells,when oxygen is NOT available in the cell. The reaction occurs in the cytosol of the cell and the products formed in plant and animal cells are different.

In Plant Cells


In plant and yeast cells, energy-rich glucose is broken down to ethanol(alcohol). Carbon dioxide and some energy is released. The process is called alcoholic fermentation.

Beer Making


Beer is made when the yeast (fungus) is allowed to ferment under anearobic conditions (absence of oxygen)to produce alcohol.

Bread Making


Yeast is also used in the making of bread. The yeast breaks down the sugar via anearobic respiration to produce ethanol and CO2. The alcohol evapourates while the CO2 forms pockets of "air",causing the dough to rise. The yeast is killed by the time the bread is fully baked.

In Animal Cells


In animal cells, anaerobic respiration is also known as lactic acid fermentation. During this process,food (eg. Glucose) is broken down to yield some energy and lactic acid.A build-up of lactic acid in muscles leads to pain and muscle cramps. N.B. Lactic acid can be converted back to pyruvic acid when oxygen becomes available,so that aerobic respiration may continue.