Question

A yeast cell feeding on glucose suddenly switches from producing carbon dioxide and many ATP molecules to producing ethyl alcohol and few ATP molecules which of the following would force to yeast to make this change

Answer 1

The most appropriate reason for this would be the moving of yeast to anaerobic respiration from aerobic respiration.

Yeast can perform both aerobic and anaerobic respiration. In aerobic respiration, yeast is able to oxidize glucose completely in presence of oxygen. It produces carbon dioxide, water and a large number of ATP (approximately 36-38 per molecule of glucose).

In contrast, under anaerobic conditions, yeast converts glucose into alcohol and produce only two molecules of ATP per glucose molecule.

Answer 2

There are two types of fermentation carried out here and are also defined by the types of products generated at the end of the process. During aerobic fermentation, Co2 and ATP are produced while when air is not present, metabolites such as ethyl alcohol and few ATP are generated. The answer is shift from aerobic to anaerobic environment.