Q: Which of the following is a correct summary of the net reaction for aerobic respiration of glucose?

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

Question 1

Which of the following statements best describes substrate-level phosphorylation in bacterial metabolism?

Accepted Answer

It involves the direct transfer of a phosphate group from a phosphorylated intermediate to ADP, forming ATP, and occurs in the cytoplasm during glycolysis.

Question 2

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

Accepted Answer

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

Question 3

Which molecule acts as the primary electron carrier during glycolysis and the citric acid cycle?

Accepted Answer

NAD+

Question 4

In the electron transport chain, what is the main consequence of electron flow from NADH to oxygen?

Accepted Answer

Generation of a proton motive force across the membrane

Question 5

Which of the following is a key difference between fermentation and aerobic respiration in bacteria?

Accepted Answer

Fermentation uses an organic molecule as the terminal electron acceptor, while aerobic respiration uses $$O_2.$$

Question 6

Which of the following best describes the fate of pyruvate under anaerobic conditions in bacteria?

Accepted Answer

It is reduced to fermentation products such as lactate or ethanol, regenerating NAD+.

Question 7

Which of the following is NOT a product of the citric acid cycle per turn (per acetyl-CoA)?

Accepted Answer

2 ATP

Question 8

A bacterium is growing in an environment lacking oxygen but containing nitrate ($$NO_3$$^-$$). Which metabolic process is it most likely using for energy production?

Accepted Answer

Anaerobic respiration

Question 9

Which of the following best explains why NAD+ is considered a recyclable cofactor in metabolism?

Accepted Answer

It shuttles electrons between reactions and is regenerated after being reduced and oxidized.

Question 10

Which of the following transport mechanisms in bacteria involves chemical modification of the transported substance?

Accepted Answer

Group translocation

Question 11

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

Accepted Answer

It is generated by the electron transport chain and used to drive ATP synthesis.

Question 12

Which of the following molecules contains the highest energy phosphate bond, based on the provided $$	riangle G^\prime$$ values?

Accepted Answer

Phosphoenolpyruvate

Question 13

A mutation in a bacterium prevents the regeneration of NAD+ during glycolysis. What is the most likely consequence?

Accepted Answer

Glycolysis will halt due to a lack of available electron acceptors for glyceraldehyde-3-phosphate dehydrogenase.

Question 14

Which of the following is a correct summary of the net reaction for aerobic respiration of glucose?

Accepted Answer

$$C_6H_{12}O_6$ + 6O_2 ightarrow 6CO_2 + 6H_2O + 	ext{energy}$$

Question 15

Which of the following best explains why the citric acid cycle is considered a cycle?

Accepted Answer

The final product, oxaloacetate, is regenerated and used to combine with acetyl-CoA to start the cycle again.

Question 16

Which of the following is a real-world application of understanding bacterial fermentation pathways?

Accepted Answer

Production of ethanol in brewing and biofuel industries.

Question 17

Which of the following best describes the role of FADH2 in cellular respiration?

Accepted Answer

It donates electrons to the electron transport chain, contributing to the proton motive force.

Question 18

Which of the following is a correct statement about the energy yield from aerobic respiration versus fermentation?

Accepted Answer

Aerobic respiration yields significantly more ATP per glucose molecule than fermentation.

Question 19

Which of the following best explains why prokaryotes can use a variety of terminal electron acceptors in respiration?

Accepted Answer

They possess diverse electron transport chains that can utilize different inorganic molecules such as $$NO_3$$^-$$, SO_4$^{2-}$$, or $$CO_2.$$

Microbial Metabolism: Central Pathways and Energy Conservation

Study Guide - Practice Questions

Study Guide - Flashcards