Question 1

Which of the following best describes the difference between anabolic and catabolic pathways in metabolism?

Accepted Answer

Anabolic pathways build polymers from monomers, requiring energy input, while catabolic pathways break down polymers into monomers, releasing energy.

Question 2

A child climbs to the top of a slide and then slides down. Which type of energy is primarily involved at the top and during the descent?

Accepted Answer

At the top: potential energy; during descent: kinetic energy.

Question 3

Which law of thermodynamics explains why the total energy in the universe remains constant, but the quality of energy decreases?

Accepted Answer

Both the first and second laws: quantity of energy is constant, but transformations increase entropy and decrease energy quality.

Question 4

Which equation correctly represents the change in Gibbs free energy for a biological process?

Accepted Answer

$$\Delta G = \Delta H - T\Delta S$$

Question 5

Cellular respiration breaks down glucose into carbon dioxide and water. Which of the following statements about this process is correct?

Accepted Answer

It is a catabolic, exergonic, hydrolysis reaction.

Question 6

Photosynthesis uses sunlight to combine carbon dioxide and water into sugars and oxygen. Which of the following best describes this process?

Accepted Answer

Anabolic, endergonic, dehydration/condensation, nonspontaneous, $$\Delta G \u003e 0$$

Question 7

Which of the following is most often least useful to life due to its randomness?

Accepted Answer

Energy in the form of heat.

Question 8

A reaction has a $$\Delta G of$$ $$-5.6$$ kcal/mol. Which statement is most accurate?

Accepted Answer

The reaction would proceed by itself but might be very slow.

Question 9

Which statement best explains how living organisms create order while obeying the laws of thermodynamics?

Accepted Answer

Living organisms create order locally, but energy transformations generate waste heat that increases the entropy of the universe.

Question 10

Which of the following best describes energy coupling in cells?

Accepted Answer

Using an exergonic process to drive an endergonic process, often mediated by ATP.

Question 11

What is the primary function of ATP hydrolysis in cellular metabolism?

Accepted Answer

To release free energy that can be used to drive endergonic reactions.

Question 12

Which of the following statements about enzymes is correct?

Accepted Answer

Enzymes lower the activation energy barrier, speeding up reactions without being consumed.

Question 13

Vioxx and other NSAIDs are potent inhibitors of the COX-2 enzyme. High substrate concentrations reduce the efficacy of inhibition. These drugs are:

Accepted Answer

Competitive inhibitors.

Question 14

What would happen to cytoplasmic enzyme activity inside a cell if the pH changed from 7.2 to 4.0?

Accepted Answer

Enzymes would probably denature and enzymatic activity would decline.

Question 15

If you are not getting enough vitamins in your food, what are you missing?

Accepted Answer

Coenzymes.

Question 16

Which of the following best describes the effect of a competitive inhibitor on an enzyme?

Accepted Answer

It competes with the substrate for the active site, reducing enzyme activity.

Question 17

Which of the following is true about most chemical reactions in living cells?

Accepted Answer

They are not at equilibrium due to constant flow of materials.

Question 18

Which statement best explains why the oxidation of glucose to CO$$_2$$ and H$$_2O is $$highly exergonic but very slow?

Accepted Answer

Few glucose and oxygen molecules have the activation energy at room temperature.

Question 19

In an energy diagram, what is the difference between the red and black curves?

Accepted Answer

The red curve is catalyzed by an enzyme and the black curve has a higher activation energy.

Question 20

For the reaction shown in an energy diagram, which statement is true?

Accepted Answer

The greater the activation energy barrier, the slower the reaction rate.

AP Biology Chapter 8 : Metabolism

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