The process of breakdown of glucose in a cell are as follows:
The first step in the breakdown of glucose both in presence of O2 and in absence of O2 is same. In this step, glucose is broken down into pyruvate. Second step which involves further breakdown of private into simple compounds can take place in two different ways:
(a) In presence of O2: In the presence of O2, private is converted into CO2 and water. Energy released during aerobic respiration is much greater than that released during an anaerobic respiration.
(b)In absence of O2: In the absence of O2 in yeast, pyruvate is converted into ethanol and CO2 and the process is called fermentation. In absence of O2, in our muscle cells, pyruvate is converted into lactic acid. The build up of lactic acid in muscle cells causes cramps.
