Question 1

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

Accepted Answer

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

Question 2

A cyclist at the top of a hill has which type of energy, and what happens to this energy as they ride down?

Accepted Answer

Potential energy; it is converted to kinetic energy as the cyclist descends.

Question 3

Which statement best summarizes the first law of thermodynamics?

Accepted Answer

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

Question 4

According to the second law of thermodynamics, what happens during every energy transfer or transformation?

Accepted Answer

The entropy of the universe increases.

Question 5

Which equation correctly represents the change in Gibbs free energy ($$\Delta G) $$for a reaction?

Accepted Answer

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

Question 6

Which of the following is true about exergonic reactions?

Accepted Answer

They release energy and have a negative $$\Delta G.$$

Question 7

Why is metabolism in living organisms never at equilibrium?

Accepted Answer

Because living organisms are open systems, constantly exchanging energy and matter with their environment.

Question 8

Which of the following is NOT a main type of cellular work powered by ATP?

Accepted Answer

Photosynthetic work

Question 9

ATP is classified as which type of macromolecule?

Accepted Answer

Nucleic acid (nucleotide)

Question 10

How does ATP typically perform cellular work?

Accepted Answer

By phosphorylating intermediates, making them more reactive.

Question 11

Which of the following best describes the function of enzymes in biological systems?

Accepted Answer

Enzymes speed up reactions by lowering the activation energy barrier.

Question 12

What is activation energy ($$E_A) in a $$chemical reaction?

Accepted Answer

The initial energy needed to start a chemical reaction.

Question 13

Which of the following mechanisms is NOT a way that enzymes lower activation energy?

Accepted Answer

Changing the $$\Delta G of $$the reaction

Question 14

How does increasing substrate concentration affect the rate of an enzyme-catalyzed reaction?

Accepted Answer

It increases the rate up to a maximum when all enzyme active sites are occupied.

Question 15

Which of the following statements about enzyme inhibitors is correct?

Accepted Answer

Competitive inhibitors compete with the substrate for the active site.

Question 16

Allosteric regulation of an enzyme involves:

Accepted Answer

Binding of a molecule at a site other than the active site, changing enzyme shape and activity.

Question 17

The binding of oxygen to hemoglobin is an example of cooperativity because:

Accepted Answer

The binding of one oxygen molecule increases the affinity for the next oxygen molecule.

Question 18

Feedback inhibition in a metabolic pathway prevents a cell from wasting resources by:

Accepted Answer

Allowing the end product to act as a noncompetitive inhibitor of an early enzyme.

Question 19

Which of the following best explains how duplication of functional domains can lead to diversification in the tyrosine kinase family?

Accepted Answer

Duplicated domains can mutate and acquire new functions without affecting the original function.

Question 20

Which of the following is a correct summary equation for aerobic cellular respiration of glucose?

Accepted Answer

$$	ext{C}_6	ext{H}_{12}	ext{O}_6 + 6 	ext{O}_2 ightarrow 6 	ext{CO}_2 + 6 	ext{H}_2	ext{O} + 	ext{Energy}$$

Metabolism and Enzyme Function: Mini-Textbook Study Notes for General Biology

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