Unit 2 Medical BioChem Exam
Q1. Which of the following enzymes is part of the both the TCA and the electron transport
chain?
A. Succinate dehydrogenase (Complex II)
Q2. ATP is used to carry energy within the cell. The majority of the energy in ATP is stored
within which of the following bonds indicated on the image below?
A. (showing molecule of ATP) Answer is 1, the arrow pointing to P-O bond.
Q3. In the case of a deficiency in phenylalanine hydroxylase which of the following amino acids
will become essential?
A. Tyrosine
Q4. The mechanism of action of the Pyruvate Dehydrogenase (PDC) relies on the use of three
prosthetic groups in the enzyme active site. Which of the following is of the PDC?
A. Cobalamin
Q5. Which of the following digestive enzymes is primarily responsible for digesting large
polysaccharide chains into smaller oligosaccharides?
A. Alpha Amylase
Q6. Which of the following tissues uses lactate from the Cori Cycle to make glucose?
A. Liver
Q7. Hereditary fructose intolerance (HFI) is a rare recessive disorder. Which of the following is
not a consequence of this enzyme deficiency?
A. Inability to metabolize glucose in skeletal muscle
Q8. NADH generated in the cytosol must be transported across the mitochondrial membrane in
order to be oxidized by the electron transport chain. Which of the following facilitate the
movement of cytosolic NADH into the mitochondria?
A. Glycerol 3-phosphate shuttle
Q9. Which of the following activators is correctly paired with the enzyme that it activates?
A. fructose-2,6-bisphosphate: phosphofructokinase 1
Q10. You have identified a mutation in the c subunit in the ATP synthase. The mutation changes the
glutamate residue, (that facilitates proton pumping into the mitochondrial matrix), to a glycine. The
inability to dissipate the proton gradient will have which of the following impacts on the electron
transport chain?
A. Increased ATP synthase (production)
Q11. Under conditions when a cell only needs to use the nonoxidative portion of the Pentose
Phosphate Pathway to synthesize ribose-5-phosphate, the elevated levels of NADPH in the cell will
inhibit which of the following enyzymes?
A. Glucose 6-phosphate dehydrogenase
