Question 1

Which of the following best describes the difference between catabolic and anabolic pathways in microbial metabolism?

Accepted Answer

Catabolic pathways break down larger molecules into smaller products and release energy, while anabolic pathways use energy to build larger molecules from smaller ones.

Question 2

Which molecule acts as the primary energy currency in microbial cells, storing energy in high-energy phosphate bonds?

Accepted Answer

ATP

Question 3

During glycolysis, what is the net gain of ATP and NADH molecules from one molecule of glucose?

Accepted Answer

$$2$$ ATP and $$2$$ NADH$

Question 4

Which of the following statements about enzymes is TRUE?

Accepted Answer

Enzymes lower the activation energy required for a reaction to proceed.

Question 5

Which of the following is a correct description of substrate-level phosphorylation?

Accepted Answer

ATP is produced by the direct transfer of a phosphate group from a substrate to ADP.

Question 6

In the electron transport chain, what is the primary function of the proton gradient?

Accepted Answer

To power ATP synthase for the phosphorylation of ADP to ATP.

Question 7

Which of the following is NOT a product of the Krebs cycle per molecule of glucose?

Accepted Answer

$$4$$ $$FADH_2$

Question 8

Which electron carrier is reduced during glycolysis and the Krebs cycle, and donates electrons to the electron transport chain?

Accepted Answer

NADH

Question 9

A competitive inhibitor of an enzyme acts by:

Accepted Answer

Binding to the active site and preventing substrate binding.

Question 10

Which of the following best explains why fermentation is necessary in some cells?

Accepted Answer

Fermentation regenerates NAD+ needed for glycolysis to continue in the absence of oxygen.

Question 11

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

Accepted Answer

Glycolysis → Synthesis of Acetyl-CoA → Krebs cycle → Electron Transport Chain

Question 12

Which of the following is a function of feedback inhibition in metabolic pathways?

Accepted Answer

It prevents the overproduction of the end product by inhibiting an early enzyme in the pathway.

Question 13

Which of the following statements about the electron transport chain (ETC) is correct?

Accepted Answer

The ETC uses the energy from electrons to pump protons across a membrane, creating a proton gradient.

Question 14

Which of the following is NOT a type of enzyme inhibition?

Accepted Answer

Substrate inhibition

Question 15

Which of the following is a true statement about the pentose phosphate pathway?

Accepted Answer

It produces NADPH and pentoses and operates alongside glycolysis.

Question 16

Which of the following is the final electron acceptor in aerobic respiration?

Accepted Answer

Oxygen ($$O_2)$$

Question 17

Which of the following is a product of lactic acid fermentation?

Accepted Answer

Lactic acid

Question 18

Which of the following best describes oxidative phosphorylation?

Accepted Answer

ATP synthesis powered by the flow of protons down their gradient through ATP synthase.

Question 19

Which of the following is a correct pairing of an electron carrier and its reduced form?

Accepted Answer

NAD+ and NADH

Question 20

A bacterium is growing in an environment without oxygen and uses nitrate ($$NO_3$$^-$$) as its final electron acceptor. Which process is this bacterium using?

Accepted Answer

Anaerobic respiration

Microbial Metabolism: Pathways, Enzymes, and Energy Production

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