Question

24.A reaction has a deltaG of 5.6 kcal/mol. Which of the following would most likely be true?

A. The reaction would result in products with a greater free-energy than in the reactants.

B. The reaction could be coupled to and thus powered by another reaction with a deltaG of -1.0 kcal/mol.

C. The reaction would release free energy.

D. The reaction is spontaneous.

E. The reaction is exergonic.

26. If we follow the oxidation of just one molecule of glucose, how many net ATP have been formed up to the end of the citric acid cycle?

A. 3

B. 2

C. 4

D. 5

E. 8

31.The Na+/K+ pump consummes a considerable amount of the total ATP produced by the cell (~30% for most cells and up to 70% in neurons), so this pump is critical for cellular function. Which of the following is true?

A. This pump contributes to a positive interior charge and thus resets the resting membrane potential of a neuron.

B. This pump is an example of passive transport.

C. This pump is a channel protein.

D. In the animal gut, the Na+ gradient generated by this pump is used to actively move glucose into the cell via coupled transport.

E. This pump hydrolyzes two ATP for each cycle through its conformations to move three Na+ ions and two K+ ions.

33. Which of the following is false regarding the structure of aquaporin?

A. The pore of this channel is selective and only allows water to cross the membrane.

B. The transmembrane portions of this channel that interact with the nonpolar tails of phospholipids are expected to be mostly hydrophobic amino acids.

C. This is an integral membrane protein that provides a pore through the membrane.

D. The pore of this channel is expected to be lined with hydrophobic amino acids.

34. Which of the following statements is a correct distinction between autotrophs and heterotrophs?

A. Only heterotrophs require oxygen.

B. Only autotrophs have mitochondria.

C. Heterotrophs can nourish themselves beginning with CO2 and other nutrients that are inorganic.

D. Autotrophs are the ultimate source of organic compounds for heterotrophs.

E. Cellular respiration is unique to heterotrophs.

34.The Calvin cycle could not occur without the light reactions. Which of the following statements describes why this is the case?

A. ADP and NADH produced in the light reactions provide the energy for the production of sugars in the Calvin cycle.

B. ATP and NADPH produced in the light reactions provide the energy for the production of sugars in the Calvin cycle.

C. ADP and NADP+ produced in the light reactions provide the energy for the production of sugars in the Calvin cycle.

D. Molecular oxygen produced in the light reactions provides the energy for the production of sugars in the Calvin cycle.

E. Photons of light directly activate the enzymes of the Calvin Cycle.

37. The oxygen consumed during cellular respiration is converted to.....
A. NAD+

B. water

C. the organic fuel (ie, glucose)

D. carbon dioxide

E. ATP

Answer 1