When O2 is added to the anaerobic suspension of cells consuming glucose at a high rate, the rate of glucose consumption declines greatly as the O2 is used up and accumulation of the lactate ceases. This effect, first observed by Louis Pasteur in the year 1860s, is characteristic of most cells capable of both the aerobic and anaerobic glucose catabolism.

a) describe why does the accumulation of lactate cease after O2 is added?

b) describe why does the presence of O2 reduce the rate of glucose consumption?

c) describe how does the onset of O2 consumption slow down the rate of glucose consumption? Describe in terms of specific enzymes.