Hydrolysis of ATP to ADP and $$\text{P}_i.$$

$$\Delta G = -100 - (300 \times 0.2) = -160 kJ/$$mol

Question 1

Which of the following best defines 'metabolism' in biological systems?

Accepted Answer

The sum of all chemical reactions, both anabolic and catabolic, occurring within a cell.

Question 2

Which statement correctly distinguishes between kinetic and potential energy?

Accepted Answer

Kinetic energy is the energy of motion, while potential energy is stored in chemical bonds.

Question 3

Which of the following best describes the first law of thermodynamics?

Accepted Answer

Energy cannot be created or destroyed, only transformed from one form to another.

Question 4

A cell synthesizes glucose from smaller molecules. This process is best described as:

Accepted Answer

Anabolic and endergonic.

Question 5

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

Accepted Answer

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

Question 6

Which of the following reactions is most likely to be spontaneous?

Accepted Answer

A reaction with $$\Delta G \u003c 0.$$

Question 7

Which statement best explains why living organisms can maintain order despite the second law of thermodynamics?

Accepted Answer

Organisms increase entropy in their surroundings while maintaining or decreasing entropy within themselves.

Question 8

Which of the following is true about ATP hydrolysis?

Accepted Answer

It releases energy that can be used to drive cellular work.

Question 9

Which of the following best describes phosphorylation?

Accepted Answer

The addition of a phosphate group to a molecule, often making it more reactive.

Question 10

Which of the following is an example of an exergonic reaction in cells?

Accepted Answer

Hydrolysis of ATP to ADP and $$	ext{P}_i.$$

Question 11

A reaction has $$\Delta H = -100 kJ/$$mol and $$\Delta S = +0.2 kJ/($$mol\cdot K). At $$T = 300 K$$, what is $$\Delta G$$?

Accepted Answer

$$\Delta G = -100 - (300 	imes 0.2) = -160 kJ/$$mol

Question 12

Which of the following statements about entropy is correct?

Accepted Answer

Entropy is a measure of disorder or randomness in a system.

Question 13

Which process is most likely to be endergonic?

Accepted Answer

Synthesis of ATP from ADP and $$	ext{P}_i.$$

Question 14

Which of the following best describes catabolic reactions?

Accepted Answer

They break down complex molecules into simpler ones, releasing energy.

Question 15

If a reaction in a cell is coupled to ATP hydrolysis, what is the main purpose of this coupling?

Accepted Answer

To provide energy to drive an endergonic reaction.

Question 16

Which of the following is true about the second law of thermodynamics?

Accepted Answer

Energy transformations increase the disorder (entropy) of the universe.

Question 17

Which of the following best explains why ATP is considered the 'energy currency' of the cell?

Accepted Answer

ATP can be hydrolyzed to release energy that is easily used for cellular work.

Question 18

Which of the following is a correct statement about exergonic and endergonic reactions?

Accepted Answer

Exergonic reactions release energy; endergonic reactions require energy input.

Question 19

Which of the following best describes the role of enzymes in metabolism?

Accepted Answer

Enzymes decrease the activation energy, speeding up chemical reactions.

Question 20

A patient is unable to efficiently break down glucose due to a metabolic disorder. Which process is most directly affected?

Accepted Answer

Catabolic breakdown of glucose to release energy.

Energy, Metabolism, and Thermodynamics in Biology: Study Guide

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