BCHM2072/ THEORY PAPER MCQs

1. An ANABOLIC pathway uses compounds X and Y to produce compounds A and B. Which statement is TRUE? A.An increase in the rate of this pathway would cause a decrease in [ADP] B.An increase in the rate of this pathway would cause a parallel decrease in the rate of fuel oxidation C.An increase in the rate of this pathway would require an increased supply of NAD D.The conversion of A & B to X & Y would be a catabolic pathway E.Either X or Y must be a macromolecule So X + Y  A + B is anabolic and requires energy    

2. Which of the following statements about ATP is TRUE? A.A solution of ATP at room temperature will spontaneously hydrolyse to give ADP and phosphate B.The turnover of ATP (ie the total amount that gets degraded and recreated per day) is about 50 g C.During times of need, ATP can be produced by one tissue and transported through the bloodstream to other tissues D.ATP can be stored in Golgi membrane vesicles for use during periods of high energy demand E.The total concentration of adenine nucleotides in a healthy cell (ie [ADP] + [ATP] + [AMP] is always about 4-6 mM    

3. Both fatty acids and carbohydrate can be oxidized to carbon dioxide with the concomitant consumption of oxygen. Which of the following is NOT a feature common to BOTH processes? A.The formation of acetyl CoA in the mitochondria B.The generation of ATP in the cytoplasm C.Trapping through the addition of polar residues after transport from the blood into the cytoplasm D.A dependence on the availability of NAD E.The net production of water during the whole process 

4. Which statement regarding the macromolecular fuel stores is FALSE? A.Glycogen, but not fat, is stored in association with water B.One gram of fat releases over twice as much energy than the same amount of glycogen C.The total mass of fat in the human body is about fold higher than that the total mass of body glycogen D.If all our energy was stored as glycogen, we would weigh at least 40 kg more than we do now E.Fat, but not glycogen, can be transported from liver to other tissues T T F T T

5. Which one of the following rules/relationships is INCORRECT? A.ADP is used when protons flow through the F 0 F 1 ATPase B.Proton re-entry into the matrix and ATP synthesis must occur simultaneously C.A molecule of ATP is formed each time a proton is pumped out of the matrix D.NADH cannot give hydrogens directly to oxygen E.Movement of hydrogens/electrons down the electron transport chain can only occur if protons are simultaneously being pumped from the matrix 

Consider a suspension of brown adipocytes, supplied with plenty of oxygen and fuels. 6. What factor is most likely to limit the rate of fuel oxidation under these conditions? A.The availability of glucose B.The availability of NADH C.The availability of acetyl CoA D.The availability of ADP E.The availability of fatty acids    

The aforementioned adipocytes were treated separately with each of the compounds below: A.Rotenone: an inhibitor of electron transport within Complex I B.Noradrenalin: an activator of the beta-3 receptors on brown adipocytes C.Methylene Blue: an acceptor of electrons from cytochrome c D.Fluoroacetate: an inhibitor of the Kreb’s Cycle E.Oligomycin: An inhibitor of the F 0 F 1 ATPase Will block fuel oxidation, oxygen consumption and lead to decreased ATP Will cause uncoupling. Massive rate of oxygen consumption and fuel oxidation. Will allow everything (electron transport, ATP synthesis, etc) to continue but oxygen consumption will stop Will block fuel oxidation. No NADH to supply electron transport. ATP synthesis stops Proton gradient will remain high. Proton pumping will stop. Fuel oxidn stops.

7.Which compound (A - E) would result in the highest rate of oxygen consumption? 8.Which compound (A - E) would result in the highest rate of ATP synthesis? 9.Which compound (A – E) would (after a few minutes) result in the largest proton gradient (largest difference in the [H+] across the matrix membrane)? 10.Which compound (A – E) would cause both ubiquinone and cytochrome c to become fully oxidised? The uncoupler, B Business as usual, C Inhibitor of use of proton gradient, E Something that stops supply of H/e to the chain, D