$$\text{Glucose} + 2 \text{ADP} + 2 \text{P}_i + 2 \text{NAD}^+ \rightarrow 2 \text{Pyruvic acid} + 2 \text{ATP} + 2 \text{NADH} + 2 \text{H}^+$$

The final electron acceptor is $$\text{O}_2$$, forming $$\text{H}_2\text{O}.$$

Question 1

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

Accepted Answer

ATP stores energy released from catabolic reactions and provides energy for anabolic reactions.

Question 2

Which equation correctly represents the net reaction of glycolysis?

Accepted Answer

$$	ext{Glucose} + 2 	ext{ADP} + 2 	ext{P}_i + 2 	ext{NAD}^+ ightarrow 2 	ext{Pyruvic acid} + 2 	ext{ATP} + 2 	ext{NADH} + 2 	ext{H}^+$$

Question 3

A competitive inhibitor of an enzyme acts by:

Accepted Answer

Binding to the active site and preventing substrate binding.

Question 4

Which of the following is true regarding the electron transport chain in aerobic respiration?

Accepted Answer

The final electron acceptor is $$	ext{O}_2$$, forming $$	ext{H}_2	ext{O}.$$

Question 5

Which of the following best explains why enzymes are highly specific for their substrates?

Accepted Answer

The active site of an enzyme has a unique three-dimensional shape that fits only specific substrates.

Question 6

Which of the following statements about feedback inhibition is correct?

Accepted Answer

The end-product of a metabolic pathway inhibits the first enzyme in the pathway by binding to its allosteric site.

Question 7

Which of the following is a correct description of oxidative phosphorylation?

Accepted Answer

ATP is generated using energy derived from the electron transport chain and chemiosmosis.

Question 8

A bacterium is found to use $$	ext{NO}_3^- as a $$final electron acceptor in its electron transport chain. Which process is this organism using?

Accepted Answer

Anaerobic respiration

Question 9

Which of the following best describes the difference between catabolism and anabolism?

Accepted Answer

Catabolism releases energy by breaking down molecules; anabolism uses energy to build complex molecules.

Question 10

Which of the following is a product of the Krebs cycle?

Accepted Answer

$$	ext{NADH}$$

Question 11

Which of the following statements about fermentation is correct?

Accepted Answer

Fermentation uses an organic molecule as the final electron acceptor.

Question 12

Which of the following is a function of the pentose phosphate pathway?

Accepted Answer

It produces NADPH and pentoses for biosynthesis.

Question 13

Which of the following best describes the effect of increasing substrate concentration on enzyme activity, as shown in the Michaelis-Menten curve?

Accepted Answer

The reaction rate increases until the enzyme is saturated, then levels off.

Question 14

Which of the following is true about the role of coenzymes in enzymatic reactions?

Accepted Answer

Coenzymes often act as electron carriers and are derived from vitamins.

Question 15

Which of the following is an example of substrate-level phosphorylation?

Accepted Answer

ATP generation during glycolysis by direct transfer of a phosphate group from phosphoenolpyruvate (PEP) to ADP.

Question 16

Which of the following best explains why high temperatures can denature enzymes?

Accepted Answer

High temperatures disrupt the hydrogen and ionic bonds maintaining the enzyme's three-dimensional structure.

Question 17

Which of the following is a correct summary of the light-dependent reactions of photosynthesis?

Accepted Answer

They convert light energy into chemical energy in the form of ATP and NADPH.

Question 18

Which of the following is a distinguishing feature of chemoheterotrophs?

Accepted Answer

They obtain both energy and carbon from organic compounds.

Question 19

A patient is given sulfanilamide to treat a bacterial infection. This drug acts as a competitive inhibitor by mimicking which bacterial substrate?

Accepted Answer

PABA (para-aminobenzoic acid)

Microbial Metabolism: Foundations and Pathways

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