Fermentation occurs in yeast, bacteria and animal cells also. It is partial oxidation of glucose.

Fermentation: Involves release of CO2

Fermentation is a metabolic process that occurs in both prokaryotic and eukaryotic organisms. It is an anaerobic process, meaning it takes place in the absence of oxygen. During fermentation, organic compounds, such as glucose, are broken down into simpler compounds, releasing energy in the process. One of the byproducts of fermentation is the release of carbon dioxide (CO2).

Key Points:
- Fermentation occurs in both prokaryotes and eukaryotes.
- It is an anaerobic process.
- Organic compounds, such as glucose, are broken down during fermentation.
- Energy is released during fermentation.
- Carbon dioxide is one of the byproducts of fermentation.

Explanation:
Fermentation is a vital metabolic process that allows cells to produce energy in the absence of oxygen. It is commonly observed in microorganisms like bacteria and yeast, but it also occurs in certain tissues of multicellular organisms, including humans.

During fermentation, glucose or other organic substrates are partially oxidized, leading to the production of energy in the form of ATP (adenosine triphosphate). This process is different from cellular respiration, which is an aerobic process that occurs in the presence of oxygen and involves the complete oxidation of glucose to produce carbon dioxide and water.

In the case of fermentation, the breakdown of glucose is incomplete and stops at an earlier stage. This is because the absence of oxygen prevents the complete oxidation of glucose. Instead, the glucose molecule is partially broken down into simpler compounds, such as ethanol or lactic acid, depending on the organism and the specific type of fermentation.

One of the common features of fermentation is the release of carbon dioxide. This is particularly evident in alcoholic fermentation, where yeast cells convert glucose into ethanol and carbon dioxide. The presence of carbon dioxide is responsible for the bubbling and foaming often observed during the fermentation of bread dough or the production of alcoholic beverages.

In summary, fermentation is a metabolic process that occurs in both prokaryotes and certain tissues of multicellular organisms. It is an anaerobic process that involves the partial oxidation of glucose or other organic compounds, leading to the release of energy and the production of simpler compounds, including carbon dioxide.