Question 1

Which of the following best describes the Second Law of Thermodynamics as it applies to biological systems?

Accepted Answer

Energy will always become more spread out and entropy will increase in spontaneous processes.

Question 2

A reaction has a negative change in Gibbs Free Energy ($$\Delta G \u003c 0). $$Which of the following statements is TRUE about this reaction?

Accepted Answer

It is exergonic and occurs spontaneously.

Question 3

Which of the following is an example of potential energy in a biological system?

Accepted Answer

Chemical bonds in a glucose molecule

Question 4

Which of the following best explains how enzymes speed up chemical reactions?

Accepted Answer

They lower the activation energy ($$E_a) $$required for the reaction to proceed.

Question 5

A competitive inhibitor affects an enzyme by:

Accepted Answer

Binding to the active site, blocking substrate binding.

Question 6

Which of the following statements about ATP hydrolysis is correct?

Accepted Answer

ATP hydrolysis couples to endergonic reactions to provide energy.

Question 7

A cell is exposed to a non-competitive inhibitor. What is the most likely effect on the enzyme's activity?

Accepted Answer

The enzyme's activity will decrease regardless of substrate concentration.

Question 8

Which of the following best describes an anabolic pathway?

Accepted Answer

Builds complex molecules from simpler ones, requiring energy input.

Question 9

A mutation causes an enzyme to lose its ability to bind cofactors. What is the most likely consequence?

Accepted Answer

The enzyme's activity will decrease or stop.

Question 10

Which of the following is a correct statement about entropy ($$S) in $$biological systems?

Accepted Answer

Entropy is a measure of disorder; it increases in spontaneous processes.

Question 11

A metabolic pathway is regulated by feedback inhibition. Which of the following best describes this process?

Accepted Answer

The end product of the pathway inhibits an early enzyme in the pathway.

Question 12

Which of the following is NOT a function of the smooth endoplasmic reticulum (ER) in eukaryotic cells?

Accepted Answer

Protein synthesis for secretion

Question 13

Which of the following best explains why cells are small in size?

Accepted Answer

Smaller cells have a higher surface area to volume ratio, allowing efficient exchange of materials.

Question 14

Which of the following is a correct pairing of a macromolecule and its function?

Accepted Answer

Proteins: Catalyze chemical reactions

Question 15

Which of the following statements about ATP is TRUE?

Accepted Answer

ATP consists of adenine, ribose, and three phosphate groups.

Question 16

A cell is exposed to extreme heat, causing its enzymes to denature. What is the most likely effect on metabolic reactions?

Accepted Answer

Metabolic reactions will slow down or stop.

Question 17

Which of the following best describes the role of mitochondria in eukaryotic cells?

Accepted Answer

They generate ATP through cellular respiration.

Question 18

Which of the following is a correct description of a chemoautotroph?

Accepted Answer

Uses energy from breaking down molecules and CO$$_2 as a $$carbon source.

Question 19

Which of the following statements about nonpolar covalent bonds is correct?

Accepted Answer

They involve equal sharing of electrons between atoms.

Question 20

A scientist discovers a new protein that is only active when phosphorylated. What type of regulation is this an example of?

Accepted Answer

Protein modification

General Biology Study Notes: Energy, Enzymes, Cell Structure, and Metabolism

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