Question 1

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

Accepted Answer

Catabolic pathways release energy by breaking down complex molecules, while anabolic pathways consume energy to build complex molecules.

Question 2

A firefly produces light through a chemical reaction. This is an example of:

Accepted Answer

Conversion of chemical energy to light energy.

Question 3

According to the first law of thermodynamics, which of the following statements is true?

Accepted Answer

Energy can be transferred and transformed, but it cannot be created or destroyed.

Question 4

Which of the following equations correctly represents the change in free energy ($$\Delta G) $$for a chemical reaction?

Accepted Answer

$$\Delta G = G_{final} - G_{initial}$$

Question 5

A reaction has a $$\Delta G of -10 kJ/$$mol. Which of the following is true about this reaction?

Accepted Answer

It is spontaneous and releases energy.

Question 6

Which of the following best explains why ATP has so much potential energy?

Accepted Answer

The three phosphate groups are negatively charged and closely packed, creating repulsion.

Question 7

What is the immediate result of ATP hydrolysis in a cell?

Accepted Answer

ATP is converted to ADP and inorganic phosphate, releasing energy.

Question 8

Which of the following statements about enzymes is correct?

Accepted Answer

Enzymes lower the activation energy barrier, speeding up reactions.

Question 9

A competitive inhibitor decreases the rate of an enzyme-catalyzed reaction by:

Accepted Answer

Binding to the active site and preventing substrate binding.

Question 10

Which of the following is an example of feedback inhibition?

Accepted Answer

The end product of a metabolic pathway inhibits an enzyme that acts early in the pathway.

Question 11

Which of the following best describes the role of cofactors in enzyme activity?

Accepted Answer

Cofactors are nonprotein molecules that help enzymes catalyze reactions.

Question 12

A scientist increases the substrate concentration in an enzyme-catalyzed reaction, but the reaction rate does not increase. What is the most likely explanation?

Accepted Answer

The enzyme is saturated with substrate.

Question 13

Which of the following is true about allosteric regulation of enzymes?

Accepted Answer

A regulatory molecule binds to a site other than the active site, affecting enzyme function.

Question 14

Which of the following best explains why organisms are considered 'islands of low entropy'?

Accepted Answer

Organisms maintain order internally while increasing the entropy of their surroundings.

Question 15

Which of the following is an example of energy coupling in cells?

Accepted Answer

Using the energy released from ATP hydrolysis to drive the synthesis of glutamine from glutamic acid and ammonia.

Question 16

Which of the following statements about spontaneous processes is correct?

Accepted Answer

Spontaneous processes increase the entropy of the universe.

Question 17

Which of the following is true about the effect of temperature on enzyme activity?

Accepted Answer

Each enzyme has an optimal temperature at which its activity is greatest.

Question 18

Which of the following best describes the induced fit model of enzyme function?

Accepted Answer

The enzyme changes shape slightly to fit the substrate more closely upon binding.

Question 19

Which of the following is a correct statement about the regeneration of ATP?

Accepted Answer

ATP is regenerated by the addition of a phosphate group to ADP, using energy from catabolic reactions.

Question 20

A patient is exposed to a toxin that irreversibly binds to the active site of an essential enzyme. What is the most likely outcome?

Accepted Answer

The enzyme will be permanently inactivated, disrupting the metabolic pathway.

Chapter 6: An Introduction to Metabolism – Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards