$$ \mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6 + 6\mathrm{O}_2 \rightarrow 6\mathrm{CO}_2 + 6\mathrm{H}_2O + \text{energy} $$

Question 1

Which statement best describes the role of enzymes in microbial metabolism?

Accepted Answer

Enzymes are organic catalysts that lower the activation energy of a reaction, speeding up metabolic processes.

Question 2

Which of the following is TRUE regarding cofactors and coenzymes in enzyme function?

Accepted Answer

Cofactors may be inorganic ions, and coenzymes are organic molecules that assist enzymes.

Question 3

A competitive inhibitor affects enzyme activity by:

Accepted Answer

Binding to the active site, preventing substrate binding.

Question 4

Which equation correctly represents substrate-level phosphorylation of ADP during glycolysis?

Accepted Answer

$$ \mathrm{ADP} + \mathrm{Pi} \rightarrow \mathrm{ATP} $$

Question 5

During glycolysis, which molecule is produced as a result of glucose breakdown?

Accepted Answer

Pyruvate

Question 6

Which of the following statements about NAD+/NADH is correct?

Accepted Answer

NAD+ accepts electrons during redox reactions, becoming NADH.

Question 7

In feedback inhibition, the end product of a metabolic pathway:

Accepted Answer

Binds to an allosteric site, changing the enzyme's shape and reducing activity.

Question 8

Which process restores redox balance during fermentation?

Accepted Answer

Conversion of pyruvate to lactic acid or ethanol, regenerating NAD+

Question 9

Which of the following is a correct description of the electron transport chain in aerobic respiration?

Accepted Answer

It uses electrons from FADH2/NADH to push H+ ions across the membrane, generating ATP via chemiosmosis.

Question 10

Which intermediate product of metabolism can be used to synthesize nucleotides?

Accepted Answer

Ribose-5-phosphate

Question 11

Which of the following correctly describes beta oxidation of fatty acids?

Accepted Answer

It reduces NAD+ and FAD to NADH and FADH2, producing acetyl-CoA.

Question 12

Which equation represents the overall reaction of aerobic respiration of glucose?

Accepted Answer

$$ \mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6 + 6\mathrm{O}_2 ightarrow 6\mathrm{CO}_2 + 6\mathrm{H}_2O + 	ext{energy} $$

Question 13

Which step in glucose catabolism produces the most ATP per molecule of glucose?

Accepted Answer

Electron transport chain and oxidative phosphorylation

Question 14

Which of the following is NOT a product of the Kreb's cycle per molecule of acetyl-CoA?

Accepted Answer

Pyruvate

Question 15

Which process involves the removal of an amino group from an amino acid, allowing it to enter the Kreb's cycle?

Accepted Answer

Deamination

Question 16

Which of the following statements about amphipathic molecules is correct?

Accepted Answer

They contain both hydrophilic and hydrophobic regions.

Question 17

Which of the following is a correct sequence of events in aerobic respiration?

Accepted Answer

Glycolysis → Kreb's Cycle → Electron Transport Chain

Question 18

Which of the following is TRUE about substrate binding to enzymes?

Accepted Answer

Binding of substrates may occur via induced fit, changing the enzyme's shape.

Question 19

Which of the following is a function of the electron carriers NAD+/NADH and FAD/FADH2 in metabolism?

Accepted Answer

They transfer electrons between metabolic reactions, participating in redox balance.

Microbial Metabolism: Enzymes, Metabolic Pathways, and Energy Production

Study Guide - Practice Questions