Question - In his studies of glucose metabolism by yeast, Louis Pasteur discovered that the sudden addition ofoxygen (O2) to a previously anaerobic suspension of yeast in grape juice resulted in a dramatic decreasein the rate of glucose consumption. This "Pasteur effect" can be counteracted by the addition of 2,4-dinitrophenol (DNP), an uncoupler of the mitochondrial electron transport chain.
(a) Why do yeast cellsconsume less glucose in the presence of oxygen? Can you estimate how much less glucose they use inthe presence of oxygen?
(b) Why does DNP counteract or prevent the Pasteur effect?