Bakers yeast is also known as Brewers yeast because it is us

Bakers yeast is also known as Brewer\'s yeast because it is used to ferment sugar sources and produce alcohol in an environment void of oxygen. Because it utilizes anaerobic fermentation to ferment sugars from grapes, the level of sugars present drop as they are broken down until a certain point where all anaerobic fermentation ceases completely, despite the fact that sufficient levels of sugar may still remain. Suggest an explanation for why this might happen.

Solution

In this example, ethanol is produced as a by product of fermentation of the anaerobic respiration. When the level of ethanol attain a certain point, then it nhibits the further growth of the yeast and enzymes.High concentrations ethanol destroys enzymes and kills the yeast cell.
So if yeast is not present and as such, there is no anaerobic respiration.