$$6 \mathrm{CO}_2 + 6 \mathrm{H}_2\mathrm{O} + \text{light energy} \rightarrow \mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6 + 6 \mathrm{O}_2$$

Question 1

Which equation correctly represents the overall process of photosynthesis in plants?

Accepted Answer

$$6 \mathrm{CO}_2 + 6 \mathrm{H}_2\mathrm{O} + 	ext{light energy} ightarrow \mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6 + 6 \mathrm{O}_2$$

Question 2

According to the second law of thermodynamics, what happens to the amount of useful energy during ordinary (non-nuclear) processes?

Accepted Answer

It decreases as energy is converted from one form to another.

Question 3

Which of the following best describes an endergonic reaction?

Accepted Answer

A reaction that requires a net input of energy from an outside source.

Question 4

What is the main role of ATP in cellular metabolism?

Accepted Answer

It acts as an energy-carrier molecule, transferring energy to drive endergonic reactions.

Question 5

Which statement about the first law of thermodynamics is correct?

Accepted Answer

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

Question 6

Which of the following is an example of kinetic energy?

Accepted Answer

The motion of molecules in a heated substance.

Question 7

Why do living organisms require a continuous input of energy?

Accepted Answer

To maintain order and synthesize complex molecules against the tendency toward disorder.

Question 8

Which of the following is NOT a form of potential energy?

Accepted Answer

The motion of a falling object.

Question 9

During photosynthesis, which molecule acts as the main energy carrier to drive the synthesis of glucose?

Accepted Answer

ATP

Question 10

Which process is an example of an exergonic reaction?

Accepted Answer

The breakdown of glucose during cellular respiration.

Question 11

What is entropy?

Accepted Answer

A measure of disorder or randomness in a system.

Question 12

Which statement best explains why all chemical reactions require activation energy?

Accepted Answer

Activation energy is needed to break existing chemical bonds before new ones can form.

Question 13

In a coupled reaction, what is the primary purpose of the exergonic reaction?

Accepted Answer

To provide the energy needed to drive the endergonic reaction.

Question 14

Which of the following best describes the role of sunlight in photosynthesis?

Accepted Answer

It provides the energy required to convert CO$$_2$$ and H$$_2O $$into glucose.

Question 15

Which of the following is a correct statement about energy transformations in living systems?

Accepted Answer

Some energy is always lost as heat during energy conversions.

Question 16

Which molecule is produced as a byproduct of photosynthesis?

Accepted Answer

$$\mathrm{O}_2$$

Question 17

Which of the following statements about chemical reactions is true?

Accepted Answer

The number and types of atoms are unchanged by the reaction.

Question 18

Which type of energy is stored in the bonds of ATP molecules?

Accepted Answer

Chemical energy

Question 19

Which of the following is a real-world example of an endergonic process in living organisms?

Accepted Answer

The synthesis of large biological molecules such as proteins.

Question 20

Which statement best describes the relationship between exergonic and endergonic reactions in cells?

Accepted Answer

Exergonic reactions provide the energy needed to drive endergonic reactions.

Energy, Thermodynamics, and Chemical Reactions in Biological Systems

Study Guide - Practice Questions