MCAT Question A Day - 5/6/14 - Answer!
Heart and liver cells can produce more ATP for each molecule of glucose than other cells in the body. This is most likely results of:
A. a more efficient ATP synthase on the outer mitochondrial membrane.
B. an additional turn of the Kreb's cycle for each glucose molecule.
C. a more efficient mechanism for moving NADH produced in glycolysis into the mitochondrial matrix.
D. production of additional NADH by the citric acid cycle.
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C is correct. This answer can most easily be found by process of elimination. Choice A is incorrect because ATP synthase is on the inner mitochondrial membrane. Choice Band D are poor answers because they mention the specific processes, Glycolysis and Krebs cycle, of which you should be familiar. A change in these processes would indicate a completely different process. Choice C, on the other hand, refers to membrane transport in a more general way allowing for the possibility that a specific mechanism of transport may differ in heart and liver cells.
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