Question 1

Which of the following types of cellular work is directly involved in muscle contraction and the movement of cellular components?

Accepted Answer

Mechanical work

Question 2

A cell is actively transporting ions to create a concentration gradient across its membrane. Which type of work is being performed?

Accepted Answer

Concentration work

Question 3

Which statement best describes the difference between phototrophs and chemotrophs?

Accepted Answer

Phototrophs use sunlight for energy, while chemotrophs use chemical compounds.

Question 4

Which of the following is TRUE regarding autotrophs?

Accepted Answer

They use carbon dioxide ($$CO_2) as $$their carbon source to synthesize organic compounds.

Question 5

According to the First Law of Thermodynamics, which of the following statements is correct?

Accepted Answer

Energy is transformed from one form to another, but the total amount remains constant.

Question 6

Which law of thermodynamics explains why ecosystems require a constant input of energy from the sun?

Accepted Answer

Second Law of Thermodynamics

Question 7

A reaction has $$\Delta H \u003e 0$$ and $$\Delta S \u003e 0. $$Under what temperature conditions will this reaction be spontaneous?

Accepted Answer

At high temperatures

Question 8

Which of the following equations correctly represents the relationship between free energy, enthalpy, and entropy?

Accepted Answer

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

Question 9

Which of the following reactions is exergonic?

Accepted Answer

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

Question 10

ATP synthesis is an endergonic process. How can cells make this reaction proceed?

Accepted Answer

By coupling it with an exergonic reaction such as ATP hydrolysis

Question 11

Which of the following best describes catabolic pathways?

Accepted Answer

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

Question 12

Which of the following is NOT a type of work performed by cells?

Accepted Answer

Photosynthesis

Question 13

In the context of energy flow in ecosystems, which statement is correct?

Accepted Answer

Energy flows unidirectionally from the sun to phototrophs, then to chemotrophs, and finally as heat.

Question 14

Which of the following is a consequence of the Second Law of Thermodynamics in biological systems?

Accepted Answer

Spontaneous processes increase the entropy of the universe.

Question 15

A cell is synthesizing a new protein from amino acids. Which type of metabolic pathway is this?

Accepted Answer

Anabolic pathway

Question 16

Which of the following statements about entropy ($$S) is $$correct?

Accepted Answer

Entropy measures the disorder of a system; higher entropy means more disorder.

Question 17

If a reaction has $$\Delta G \u003e 0$$, what does this indicate about the reaction?

Accepted Answer

The reaction is non-spontaneous and endergonic.

Question 18

Which of the following is an example of electrical work in cells?

Accepted Answer

Generation of charge gradients during nerve impulses

Question 19

Which of the following is NOT a correct statement about metabolic pathways?

Accepted Answer

Anabolic and catabolic pathways use the same enzymes and intermediates.

Question 20

Which of the following best explains why ATP hydrolysis is highly exergonic?

Accepted Answer

Because hydrolysis relieves charge repulsion between phosphate groups and increases entropy.

Cellular Energetics and Metabolism: Energy Flow, Thermodynamics, and Biochemical Pathways

Study Guide - Practice Questions