$$6CO_2 + 12H_2O + \text{light energy} \rightarrow C_6H_{12}O_6$ + 6O_2 + 6H_2O$$

Question 1

Which of the following best explains why a cheetah, as shown in the image, ultimately depends on solar energy for survival?

Accepted Answer

The cheetah preys on animals (like the impala) that eat plants, which have captured solar energy through photosynthesis.

Question 2

Which of the following is a correct representation of the overall photosynthesis reaction in plants?

Accepted Answer

$$6CO_2 + 12H_2O + 	ext{light energy} ightarrow C_6H_{12}O_6$ + 6O_2 + 6H_2O$$

Question 3

Which of the following best describes the role of ATP in cellular metabolism?

Accepted Answer

ATP stores energy in its phosphate bonds and releases it when converted to ADP.

Question 4

Which of the following statements about the laws of thermodynamics is correct?

Accepted Answer

The first law states that energy cannot be created or destroyed, only transformed.

Question 5

During which type of metabolic reaction is water produced as a byproduct?

Accepted Answer

Anabolic (dehydration synthesis) reactions

Question 6

Which of the following best describes an exergonic reaction?

Accepted Answer

A reaction in which energy is released and the reactants have more energy than the products

Question 7

Which of the following is an example of a redox reaction in cellular metabolism?

Accepted Answer

The breakdown of glucose to carbon dioxide and water during cellular respiration

Question 8

What is the main function of enzymes in metabolic pathways?

Accepted Answer

To catalyze and speed up specific biochemical reactions by lowering activation energy

Question 9

Which of the following factors can cause irreversible denaturation of enzymes?

Accepted Answer

Heavy metals such as mercury or lead

Question 10

Which of the following best describes the difference between competitive and non-competitive enzyme inhibition?

Accepted Answer

Competitive inhibitors bind to the active site, while non-competitive inhibitors bind to an allosteric site.

Question 11

Which of the following is a correct statement about the flow of energy in ecosystems?

Accepted Answer

Energy flows in one direction, with most being lost as heat at each transfer.

Question 12

Which of the following best explains why anabolic reactions are considered endergonic?

Accepted Answer

They require an input of energy to build complex molecules from simpler ones.

Question 13

Which of the following is a function of coenzymes such as NADH and FADH2 in metabolism?

Accepted Answer

They serve as electron carriers in redox reactions.

Question 14

A patient is exposed to a high dose of arsenic. Which of the following is the most likely effect on their cellular metabolism?

Accepted Answer

Irreversible inhibition of enzymes, leading to cell death

Question 15

Which of the following best describes the relationship between catabolism and anabolism in metabolism?

Accepted Answer

Catabolism releases energy by breaking down molecules, and anabolism uses that energy to build new molecules.

Question 16

Which of the following is an example of a potential energy source in a cell?

Accepted Answer

Chemical bonds in glucose molecules

Question 17

Which of the following best explains why cells do not spontaneously combust, even though catabolic reactions increase entropy?

Accepted Answer

Catabolic reactions are regulated by activation energy and enzymes, preventing uncontrolled reactions.

Question 18

Which of the following is a correct statement about enzyme specificity?

Accepted Answer

Each enzyme catalyzes only a specific reaction with a specific substrate.

Question 19

Which of the following best describes the effect of increasing substrate concentration on enzyme activity in the presence of a competitive inhibitor?

Accepted Answer

Enzyme activity can increase if substrate concentration is high enough to outcompete the inhibitor.

Question 20

Which of the following best describes the role of activation energy in chemical reactions?

Accepted Answer

It is the energy required to start a reaction, which enzymes help to lower.

Cells & Energy: Enzymes, Metabolism, and Energy Transformations

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