Fermentative processes lead to the formation of small organic molecules, but still capable of releasing energy.
For example, ethyl alcohol, one of the products of glucose fermentation, contains reasonable amounts of releasable energy, both used as fuel.Aerobic respiration consists in carrying out the process of degradation of organic molecules, reducing them to virtually no release energy. The initial degradation products of the organic molecule are combined with oxygen from the air and transformed into carbon dioxide and water.
The aerobic respiration process is much more efficient than fermentation: For each degraded glucose molecule, 38 ATP molecules are produced in respiration from 38 ADP molecules. and 38 phosphate groups.
In fermentation, only two ATP molecules are produced for each glucose molecule used. The energy efficiency of respiration is therefore nineteen times greater than that of fermentation.
Aerobic respiration is a much more complex process than fermentation. It takes about 60 additional metabolic steps, in addition to the nine that make up glycolysis, for a glucose molecule to be completely degraded to CO2 and H2O in the presence of O2.
Aerobic Breath Steps
The degradation of glucose in cellular respiration occurs in three fundamental stages: glycolysis, Krebs cycle and chain breath. Glycolysis occurs in the cell's hyaloplasma, while the Krebs cycle and respiratory chain occur within the mitochondria. We will study each of these steps below.