Question 1

Which of the following best describes the role of energy in living cells?

Accepted Answer

Cells convert various energy sources into different energy forms to perform work.

Question 2

Which type of energy is associated with the random movement of atoms or molecules?

Accepted Answer

Thermal energy

Question 3

A diver standing on a platform has more potential energy than when in the water. What happens to the diver’s energy as they jump into the water?

Accepted Answer

Potential energy is converted to kinetic energy.

Question 4

Which law of thermodynamics states that energy cannot be created or destroyed, only transformed?

Accepted Answer

The First Law of Thermodynamics

Question 5

During energy transfer in biological systems, some energy is always lost as which of the following?

Accepted Answer

Heat

Question 6

Which equation correctly represents the change in free energy for a chemical reaction?

Accepted Answer

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

Question 7

If a chemical reaction has $$\Delta G \u003c 0$$, what can be concluded about the reaction?

Accepted Answer

The reaction is exergonic and releases energy.

Question 8

Hydrogen peroxide decomposes into water and oxygen with $$\Delta G = -28.5$$ kcal/mol. Which statement is true about this reaction?

Accepted Answer

It is a spontaneous reaction.

Question 9

Which of the following best describes activation energy in a chemical reaction?

Accepted Answer

The energy required to break bonds and reach the transition state.

Question 10

Why is heat not always a viable way for cells to overcome activation energy?

Accepted Answer

Heat can denature proteins and disrupt cellular processes.

Question 11

Which of the following statements about exergonic reactions is correct?

Accepted Answer

Exergonic reactions are spontaneous but may require activation energy.

Question 12

In the reaction $$2H_2O_2 \rightarrow 2H_2O + O_2$, which has more free energy: the reactants or the products?

Accepted Answer

The reactants

Question 13

Which of the following is NOT a characteristic of living organisms related to energy?

Accepted Answer

Living organisms do not require energy for cellular processes.

Question 14

Which of the following best describes a chemical reaction?

Accepted Answer

A process in which substances are changed by breaking and reforming bonds.

Question 15

Which of the following is true about endergonic reactions?

Accepted Answer

They require an input of energy to proceed.

Question 16

Which term describes the energy that matter possesses because of its location or structure?

Accepted Answer

Potential energy

Question 17

Which of the following is a correct statement about the Second Law of Thermodynamics?

Accepted Answer

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

Question 18

A cell uses energy from food to produce light. This is an example of:

Accepted Answer

Energy conversion from chemical to light energy.

Question 19

Which of the following is true about spontaneous chemical reactions?

Accepted Answer

They may require activation energy to get started.

Question 20

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

Accepted Answer

The reaction is endergonic and requires energy input.

Energy and Thermodynamics in Biological Systems

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