Biochemistry Concepts And Connections 1st Edition By Appling – Test Bank

Chapter 11 Chemical Logic of Metabolism

1) Calculate the amount of ATP in kg that is turned over by a resting human every 24 hours. Assume that a typical human contains ~50g of ATP (Mr 505) and consumes ~8000 kJ of energy in food each day. The energy stored in the terminal anhydride bond of ATP under standard conditions is 30.6 kJmol-1. Assume also that the dietary energy is channeled through ATP with an energy transfer efficiency of ~50%.
Answer: 66 kg
Objective: 11.2
Global LO: G4

2) The anabolic and catabolic processes of cellular metabolism can be coupled by ATP.
Answer: TRUE
Objective: 11.3
Global LO: G7

3) Catabolic processes involve degradation of complex molecules into simpler molecules with the net release of chemical energy.
Answer: TRUE
Objective: 11.3
Global LO: G7

4) Name the type of reaction that involves reversible electron transfer from a donor to an acceptor.
Answer: Redox, oxidation-reduction
Objective: 11.4
Global LO: G7

5) Which of the following produces the largest number of reducing equivalents when oxidized?
A) Glucose
B) NADPH
C) NADH
D) Palmitic acid
E) A hydrogen atom
Answer: D
Objective: 11.5
Global LO: G2

6) ATP has a high phosphoryl group transfer potential because:
A) it is chemically unstable.
B) it has a high rate of spontaneous hydrolysis at physiological pH and temperature.
C) it exhibits resonance stabilization prior to hydrolysis.
D) it has three phosphate groups.
E) cleavage of either of its two phosphoanhydride bonds proceeds with a large negative △Go’ of hydrolysis.
Answer: E
Objective: 11.6
Global LO: G2
7) Substrate-level phosphorylation is a term given to the loss of free energy when ATP is hydrolyzed.
Answer: FALSE
Objective: 11.6
Global LO: G7

8) The main energy-coupling compound in biochemical reactions that allows thermodynamically unfavorable processes to become favorable is ________.
Answer: ATP
Objective: 11.6
Global LO: G7

9) Under physiological conditions the complete oxidation of glucose to carbon dioxide and water in the presence of oxygen has a △G of -2900 kJ/mol glucose. This process can be coupled to the synthesis of ~32 mol ATP. The △G of the coupled reactions to make ATP is -1300 kJ/mol glucose. Calculate the △G for the synthesis of ATP from ADP.
Answer: +50 kJmol-1
Objective: 11.6
Global LO: G4

10) Which of the following can be used as a metabolic control mechanism?
A) Enzyme compartmentation
B) Action of hormones
C) Covalent modification of an enzyme
D) Regulation of enzyme degradation
E) All of the above
Answer: E
Objective: 11.7
Global LO: G7