Question 1

Which of the following best describes the difference between exergonic and endergonic reactions in terms of free energy ($$\Delta G$$)?

Accepted Answer

Exergonic reactions have a negative $$\Delta G$$ and release energy, while endergonic reactions have a positive $$\Delta G$$ and require energy input.

Question 2

A patient is diagnosed with a genetic disorder that causes their enzymes to have a significantly higher activation energy than normal. Which of the following is the most likely consequence?

Accepted Answer

The metabolic reactions will proceed much more slowly, potentially leading to metabolic disorders.

Question 3

Which of the following statements about the Second Law of Thermodynamics is correct in the context of biological systems?

Accepted Answer

Every energy transfer increases the entropy (disorder) of the universe.

Question 4

During aerobic respiration, which step is responsible for the majority of ATP production, and by what mechanism is this ATP generated?

Accepted Answer

Electron Transport Chain; oxidative phosphorylation

Question 5

Which of the following best describes allosteric regulation of an enzyme?

Accepted Answer

A molecule binds to a site other than the active site, causing a conformational change that affects enzyme activity.

Question 6

Which of the following environmental factors can impact enzyme function by altering the enzyme's three-dimensional structure?

Accepted Answer

pH and temperature

Question 7

In glycolysis, which steps are considered part of the energy investment phase, and what is the net ATP yield from glycolysis per molecule of glucose?

Accepted Answer

The first two phosphorylation steps; net yield is 2 ATP

Question 8

Which of the following correctly describes the fate of pyruvate under anaerobic conditions in human muscle cells?

Accepted Answer

Pyruvate is reduced to lactate, regenerating NAD$$^+$$ for glycolysis.

Question 9

Which of the following is a correct description of a redox reaction?

Accepted Answer

Oxidation is the loss of electrons, and reduction is the gain of electrons.

Question 10

A competitive inhibitor affects an enzyme-catalyzed reaction by:

Accepted Answer

Binding to the active site, preventing substrate binding.

Question 11

Which of the following best explains why fats yield more ATP per gram than carbohydrates during cellular respiration?

Accepted Answer

Fats are more reduced, providing more electrons for the electron transport chain.

Question 12

Which of the following is the correct overall equation for aerobic glucose metabolism?

Accepted Answer

$$\mathrm{C_6H_{12}O_6$} + 6\ \mathrm{O_2$} ightarrow 6\ \mathrm{CO_2$} + 6\ \mathrm{H_2O} + 	ext{energy (ATP)}$$

Question 13

Which step in cellular respiration produces the most NADH per glucose molecule?

Accepted Answer

Krebs (TCA) cycle

Question 14

Which of the following statements best distinguishes substrate-level phosphorylation from oxidative phosphorylation?

Accepted Answer

Substrate-level phosphorylation directly transfers a phosphate group to ADP from a substrate, while oxidative phosphorylation uses a proton gradient and ATP synthase.

Question 15

If a cell is exposed to a noncompetitive inhibitor, what is the most likely effect on the enzyme's activity?

Accepted Answer

The inhibitor binds to a site other than the active site, decreasing the maximum reaction rate ($$V_{max}).$$

Question 16

Which of the following is the maximum theoretical yield of ATP from the complete oxidation of one molecule of glucose in eukaryotic cells?

Accepted Answer

38 ATP

Question 17

During the Krebs (TCA) cycle, which steps involve the release of $$\mathrm{CO_2$}$$?

Accepted Answer

Isocitrate to alpha-ketoglutarate and alpha-ketoglutarate to succinyl-CoA

Question 18

Which of the following best explains how proteins can contribute to ATP production in cellular respiration?

Accepted Answer

Proteins are broken down into amino acids, which are deaminated and their carbon skeletons enter glycolysis or the Krebs cycle.

Question 19

Which of the following statements about fermentation is correct?

Accepted Answer

Fermentation allows glycolysis to continue by regenerating NAD$$^+ in $$the absence of oxygen.

Question 20

Which of the following best describes the role of ATP in anabolic and catabolic pathways?

Accepted Answer

ATP provides energy for anabolic pathways and is generated during catabolic pathways.

General Biology: Energy, Enzymes, and Cellular Respiration Study Guide

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드