Question 1

Which of the following is NOT a universal requirement for cellular life as discussed in Lecture 8?

Accepted Answer

Oxygen gas

Question 2

Cells conserve and store energy primarily in the form of which molecule, which is then used to fuel cellular processes?

Accepted Answer

Adenosine triphosphate (ATP)

Question 3

Which of the following best describes the role of an electron donor in cellular metabolism?

Accepted Answer

It provides electrons that are transferred to an electron acceptor.

Question 4

Which process directly generates ATP by transferring a phosphate group from a substrate to ADP?

Accepted Answer

Substrate-level phosphorylation

Question 5

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

Accepted Answer

Photoautotroph

Question 6

Which of the following statements about electron carriers is TRUE?

Accepted Answer

NAD$$^+ is $$reduced to NADH during catabolic reactions.

Question 7

The Law of the Minimum states that:

Accepted Answer

Growth is limited by the nutrient in the lowest concentration relative to need.

Question 8

Which of the following best explains why aerobic respiration yields more ATP than anaerobic respiration?

Accepted Answer

Oxygen is a more positive electron acceptor, allowing for a greater difference in reduction potential.

Question 9

Which of the following equations correctly represents the overall reaction for aerobic respiration of glucose?

Accepted Answer

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

Question 10

During oxidative phosphorylation, the proton motive force (PMF) is generated by:

Accepted Answer

The transfer of electrons through the electron transport chain, pumping protons across the membrane.

Question 11

Which of the following best describes the function of ATP synthase?

Accepted Answer

It uses the flow of protons down their gradient to catalyze the synthesis of ATP from ADP and phosphate.

Question 12

A chemoorganotroph obtains its energy and electrons from:

Accepted Answer

Organic compounds

Question 13

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

Accepted Answer

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

Question 14

Which of the following is a micronutrient required by microbes in trace amounts, often as a cofactor for enzymes?

Accepted Answer

Zinc (Zn)

Question 15

A facultative organism is best described as one that:

Accepted Answer

Can switch between different metabolic modes depending on environmental conditions.

Question 16

Which of the following statements about denitrification is TRUE?

Accepted Answer

It is the reduction of nitrate to nitrogen gas.

Question 17

Which of the following best explains why cyanide is a potent inhibitor of aerobic respiration?

Accepted Answer

It blocks the flow of electrons through the electron transport chain by binding to cytochrome oxidase.

Question 18

Which of the following best describes the difference between chemolithotrophs and chemoorganotrophs?

Accepted Answer

Chemolithotrophs use inorganic electron donors, while chemoorganotrophs use organic electron donors.

Question 19

Which of the following is a correct example of a chemoorganotroph?

Accepted Answer

Escherichia coli

Question 20

Which of the following best describes the function of the proton motive force (PMF) in microbial cells?

Accepted Answer

It is used to drive the synthesis of ATP via ATP synthase.

Microbial Metabolism: Requirements and Energy Conservation

Study Guide - Practice Questions