The yeast began its respiration aerobically, but then after time completed it anaerobically.?

Question

The yeast began its respiration aerobically, but then after time completed it anaerobically. How do these two processes differ in terms of the products and energy yielded (ATP) in this process?

Answer 1

aerobic respiration requires oxygen, but oxidizes glucose completely to CO2 and water. Different text books have different values for the amount of ATP you get from a single molecule of glucose but it'll be somewhere in the 30-36 range.

Without oxygen available, the glucose can only be fermented. Yeast ferment glucose to ethanol and CO2. In the process, a cell can produce only a net of 2 ATP per moleucle of glucose used.