Question 1

Which of the following statements best describes a key difference between prokaryotic and eukaryotic cells?

Accepted Answer

Prokaryotic cells have a single, circular chromosome located in a nucleoid region and lack membrane-bound organelles.

Question 2

Which bacterial structure is primarily responsible for resistance to phagocytosis and can act as a virulence factor?

Accepted Answer

Capsule (a type of glycocalyx)

Question 3

A patient sample reveals Gram-negative diplococci. Which of the following is most likely the causative agent?

Accepted Answer

Neisseria meningitidis

Question 4

Which of the following best explains why Gram-negative bacteria are generally more resistant to certain antibiotics than Gram-positive bacteria?

Accepted Answer

They possess an outer membrane containing lipopolysaccharide (LPS) that acts as a barrier.

Question 5

Which of the following is a function of bacterial endospores?

Accepted Answer

Allowing bacteria to survive extreme environmental conditions such as heat, desiccation, and chemicals

Question 6

A bacterium is observed to move toward a chemical attractant by alternating between runs and tumbles. What is this behavior called?

Accepted Answer

Chemotaxis

Question 7

Which of the following best describes the structure of peptidoglycan in bacterial cell walls?

Accepted Answer

A polymer of N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM) cross-linked by peptide bridges

Question 8

Which of the following is a unique feature of the cell wall of Mycobacterium tuberculosis?

Accepted Answer

Presence of mycolic acids, which are long-chain waxy lipids

Question 9

Which of the following best explains the function of bacterial plasmids?

Accepted Answer

They are extra-chromosomal DNA elements that can carry nonessential genes, such as antibiotic resistance genes.

Question 10

A Gram-positive bacterium is treated with lysozyme. What is the most likely outcome?

Accepted Answer

The peptidoglycan will be degraded, leading to the formation of a protoplast.

Question 11

Which of the following structures is directly involved in bacterial conjugation (DNA transfer between cells)?

Accepted Answer

Sex pilus (a specialized pilus)

Question 12

Which of the following best describes the process of facilitated diffusion in bacteria?

Accepted Answer

Passive movement of molecules down their concentration gradient via a specific transport protein

Question 13

Which of the following is a function of bacterial inclusions such as polyhydroxybutyrate (PHB) granules?

Accepted Answer

Storage of energy reserves

Question 14

Which of the following is evidence supporting the endosymbiotic theory for the origin of mitochondria and chloroplasts?

Accepted Answer

They have circular DNA and ribosomes similar to those of bacteria.

Question 15

A bacterium is placed in a hypertonic solution. What is the most likely effect on the cell?

Accepted Answer

Water will move out of the cell, causing plasmolysis.

Question 16

Which of the following best describes the function of the periplasmic space in Gram-negative bacteria?

Accepted Answer

It contains enzymes and proteins involved in nutrient acquisition and cell wall synthesis.

Question 17

Which of the following equations correctly represents the direction of passive diffusion across a bacterial plasma membrane?

Accepted Answer

$$[High\ concentration] \rightarrow [Low\ concentration]$$

Question 18

Which of the following is a correct statement about the function of ribosomes in prokaryotic cells?

Accepted Answer

They are the site of protein synthesis, composed of rRNA and proteins.

Question 19

A bacterium with a corkscrew motion and internal flagella is most likely a member of which group?

Accepted Answer

Spirochetes

Question 20

Which of the following best explains why endospores are highly resistant to environmental stress?

Accepted Answer

They contain dipicolinic acid (DPA) and calcium ions, and have low water content.

Functional Anatomy of Prokaryotic Cells

Study Guide - Practice Questions