Question 1

Which of the following best describes an anabolic pathway in cellular metabolism?

Accepted Answer

A pathway that synthesizes complex molecules from simpler ones, requiring energy input.

Question 2

Which of the following is an example of a catabolic pathway?

Accepted Answer

Cellular respiration breaking down glucose into $$CO_2$$ and $$H_2O.$$

Question 3

A ball rolling down a hill is an example of which type of energy?

Accepted Answer

Kinetic energy

Question 4

Which of the following best describes potential energy in biological systems?

Accepted Answer

Energy stored in chemical bonds, such as those in ATP.

Question 5

The change in Gibbs free energy ($$\Delta G) $$for a reaction is given by which equation?

Accepted Answer

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

Question 6

Which statement about exergonic reactions is correct?

Accepted Answer

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

Question 7

Endergonic reactions in cells:

Accepted Answer

Require energy input and have a positive $$\Delta G.$$

Question 8

Which of the following best describes equilibrium in a chemical reaction?

Accepted Answer

The point at which the forward and reverse reaction rates are equal.

Question 9

Activation energy is best defined as:

Accepted Answer

The minimum energy required to initiate a chemical reaction.

Question 10

According to the first law of thermodynamics, which statement is true?

Accepted Answer

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

Question 11

The second law of thermodynamics states that:

Accepted Answer

Every energy transfer increases the entropy of the universe.

Question 12

Which of the following scenarios best illustrates the concept of entropy?

Accepted Answer

A drop of dye dispersing evenly in a glass of water.

Question 13

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 14

Which of the following statements about energy transformations in living organisms is correct?

Accepted Answer

Some energy is always lost as heat, increasing entropy.

Question 15

Which process is most likely to be spontaneous at standard conditions?

Accepted Answer

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

Question 16

In a metabolic pathway, which of the following would most likely decrease the activation energy of a reaction?

Accepted Answer

Adding a catalyst such as an enzyme.

Question 17

Which of the following is true about the relationship between catabolic and anabolic pathways?

Accepted Answer

Catabolic pathways release energy, which can be used to drive anabolic pathways.

Question 18

A cell is performing a reaction with $$\Delta G = +30 kJ/$$mol. What must be true for this reaction to proceed?

Accepted Answer

The reaction is endergonic and requires coupling to an exergonic process.

Question 19

Which of the following best explains why living organisms do not violate the second law of thermodynamics?

Accepted Answer

Organisms increase the entropy of their surroundings while maintaining order internally.

Energy, Thermodynamics, and Metabolic Pathways in Biology

Study Guide - Practice Questions