Question 1

Which of the following is NOT a fundamental requirement for microbial life?

Accepted Answer

A source of light for photosynthesis

Question 2

In the aerobic respiration of glucose, what is the overall change in free energy ($$\Delta G_0$') $$under standard conditions?

Accepted Answer

$$-2895 kJ/$$mol$

Question 3

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

Accepted Answer

ATP stores energy in high-energy phosphate bonds for cellular work.

Question 4

Which of the following statements about catabolism and anabolism is CORRECT?

Accepted Answer

Catabolism generates ATP, which is then used to drive anabolic reactions.

Question 5

A microorganism that uses light as an energy source and CO$$_2 as a $$carbon source is classified as a:

Accepted Answer

Photoautotroph

Question 6

Which of the following redox couples has the greatest tendency to donate electrons based on its reduction potential ($$E_0$$'$$)?

Accepted Answer

CO$$_2/$$glucose ($$-0.43 V)$$

Question 7

Which of the following is TRUE regarding substrate-level phosphorylation?

Accepted Answer

It involves the direct transfer of a phosphate group to ADP from a phosphorylated intermediate.

Question 8

During glycolysis, what is the net yield of ATP, NADH, and pyruvate per molecule of glucose?

Accepted Answer

2 ATP, 2 NADH, 2 pyruvate

Question 9

Which of the following best explains why glycolysis alone cannot sustain life in most cells?

Accepted Answer

It does not regenerate NAD$$^+$$, leading to redox imbalance.

Question 10

Which of the following is a key difference between fermentation and respiration in microbial metabolism?

Accepted Answer

Fermentation generates ATP via substrate-level phosphorylation, while respiration uses oxidative phosphorylation.

Question 11

Which of the following is a function of the citric acid cycle (Krebs cycle) in microbial cells?

Accepted Answer

It oxidizes pyruvate to CO$$_2$$ and generates NADH and FADH$$_2$$ for the electron transport chain.

Question 12

Which of the following statements about enzymes is CORRECT?

Accepted Answer

Enzymes lower the activation energy, increasing the reaction rate.

Question 13

Which of the following best describes the role of NAD$$^+/$$NADH in microbial metabolism?

Accepted Answer

NADH acts as a soluble electron carrier, shuttling electrons between reactions.

Question 14

Which of the following is an example of a chemolithotroph?

Accepted Answer

A bacterium that oxidizes H$$_2S $$for energy

Question 15

Which of the following statements about the proton motive force (PMF) is TRUE?

Accepted Answer

PMF is used to drive ATP synthesis during oxidative phosphorylation.

Question 16

Which of the following is a correct pairing of metabolic class and energy source?

Accepted Answer

Phototroph – light

Question 17

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

Accepted Answer

Lactate

Question 18

Which of the following best explains why fermentation is less efficient than respiration in terms of energy conservation?

Accepted Answer

Fermentation only conserves a fraction of the energy in organic substrates via substrate-level phosphorylation.

Question 19

Which of the following is a role of coenzymes in enzyme catalysis?

Accepted Answer

They act as transient carriers of specific atoms or functional groups during the reaction.

Question 20

Which of the following statements about the citric acid cycle is INCORRECT?

Accepted Answer

It directly produces large amounts of ATP via substrate-level phosphorylation.

Microbial Metabolism: Fundamentals, Energy Conservation, and Catabolic Pathways

Study Guide - Practice Questions