Question 1

Which of the following best describes the main function of the cytoplasmic membrane in prokaryotic cells?

Accepted Answer

It acts as a selective permeability barrier, allowing nutrients in and waste out.

Question 2

Which chemical linkage is unique to archaeal membrane lipids, distinguishing them from bacterial and eukaryotic membranes?

Accepted Answer

Ether linkage

Question 3

A bacterium is found to have a thick peptidoglycan layer, teichoic acids, and no outer membrane. Which Gram reaction would you expect and why?

Accepted Answer

Gram-positive, because of the thick peptidoglycan and teichoic acids

Question 4

Which of the following is NOT a function of the S-layer in prokaryotes?

Accepted Answer

Serving as the main site of ATP synthesis

Question 5

Which transport system in bacteria involves the chemical modification of the transported substance and is driven by phosphoenolpyruvate?

Accepted Answer

Group translocation

Question 6

A scientist isolates a cell wall from a methanogenic archaeon and finds alternating N-acetylglucosamine and N-acetyltalosaminuronic acid. Which enzyme would NOT be effective in breaking down this wall?

Accepted Answer

Lysozyme

Question 7

Which component of the Gram-negative outer membrane is responsible for its toxicity in humans?

Accepted Answer

Lipid A

Question 8

Which of the following statements about bacterial endospores is FALSE?

Accepted Answer

They are produced by all bacteria as a survival mechanism.

Question 9

A bacterium is observed to move toward a capillary tube containing glucose. Which process is responsible for this behavior?

Accepted Answer

Chemotaxis

Question 10

Which of the following best explains why penicillin is effective against many Gram-positive bacteria but not against Archaea?

Accepted Answer

Penicillin inhibits peptide cross-linking in peptidoglycan, which Archaea lack.

Question 11

Which of the following cell surface structures is primarily involved in the formation of biofilms and attachment to surfaces?

Accepted Answer

Capsules and slime layers

Question 12

Which of the following is a unique feature of the cytoplasmic membrane of Mycoplasma species?

Accepted Answer

Incorporation of sterols for membrane stability

Question 13

Which of the following best describes the arrangement and function of bacterial flagella in peritrichous cells?

Accepted Answer

Flagella are distributed over the entire cell surface and allow 'run and tumble' motility.

Question 14

Which of the following is a function of small acid-soluble spore proteins (SASPs) in bacterial endospores?

Accepted Answer

They bind and protect DNA from damage.

Question 15

Which of the following is a key difference between bacterial and archaeal flagella (archaella)?

Accepted Answer

Bacterial flagella are composed of flagellin, while archaella are composed of proteins more closely related to pili.

Question 16

Which of the following inclusions allows aquatic bacteria to regulate their buoyancy?

Accepted Answer

Gas vesicles

Question 17

A mutation in a bacterium prevents the formation of porins. Which process would be most directly affected?

Accepted Answer

Transport of small molecules across the outer membrane

Question 18

Which of the following best explains why magnetotactic bacteria align and swim along magnetic field lines?

Accepted Answer

They use magnetosomes to orient themselves for optimal oxygen concentration.

Question 19

Which of the following is a major function of the eukaryotic cytoskeleton?

Accepted Answer

Maintaining cell shape and facilitating organelle movement

Question 20

Which evidence supports the endosymbiotic origin of mitochondria and chloroplasts?

Accepted Answer

They contain circular DNA and ribosomes similar to those of Bacteria.

Chapter 2

Study Guide - Practice Questions

Study Guide - Flashcards