EVERYDAY SCIENCE

Detailed explanation-1: -Glycolysis, which is the first step in all types of cellular respiration is anaerobic and does not require oxygen. If oxygen is present, the pathway will continue on to the Krebs cycle and oxidative phosphorylation. However, if oxygen is not present, some organisms can undergo fermentation to continually produce ATP.

Detailed explanation-2: -When oxygen is not present, pyruvate will undergo a process called fermentation. In the process of fermentation the NADH + H+ from glycolysis will be recycled back to NAD+ so that glycolysis can continue. In the process of glycolysis, NAD+ is reduced to form NADH + H+.

Detailed explanation-3: -Fermentation provides energy for cells without using oxygen. One type of fermentation occurs in yeast and some other single-celled organisms. This process is sometimes called alcoholic fermentation because alcohol is one of the products made when these organisms break down sugars.

Detailed explanation-4: -Fermentation is an anaerobic process in which energy can be released from glucose even though oxygen is not available. Fermentation occurs in yeast cells, and a form of fermentation takes place in bacteria and in the muscle cells of animals.

Detailed explanation-5: -No, fermentation does not produce or use oxygen. Instead, alcoholic fermentation produces carbon dioxide gas with ethanol.