Addition of small amounts of oxaloacetate or malate to suspensions of minced pigeon-breast muscle stimulated the oxygen consumption of the preparation. Surprisingly, when the amount of oxygen consumed was measured, it was about 7 times more than the amount necessary to oxidize the added oxaloacetate or malate completely to carbon dioxide and water.
(a) Why does the addition of oxaloacetate or malate stimulate oxygen consumption?
(b) Why is the amount of oxygen consumed so much greater than the amount necessary to oxidize the added oxaloacetate or malate completely?