Question 1

Which of the following statements best distinguishes prokaryotic cells from eukaryotic cells?

Accepted Answer

Prokaryotic cells have a single circular chromosome not enclosed by a membrane.

Question 2

A bacterium is observed to have a thick peptidoglycan layer and teichoic acids in its cell wall. Which Gram reaction will it most likely display after a Gram stain?

Accepted Answer

It will appear purple due to retention of crystal violet.

Question 3

Which of the following best describes the function of the glycocalyx in bacteria?

Accepted Answer

It contributes to virulence by preventing phagocytosis and aiding in biofilm formation.

Question 4

A patient is infected with a bacterium that is resistant to phagocytosis. Which structure is most likely responsible for this resistance?

Accepted Answer

Capsule

Question 5

Which of the following is a correct description of the arrangement of bacterial flagella?

Accepted Answer

Monotrichous: a single flagellum at one pole

Question 6

Which component of the Gram-negative bacterial cell wall is responsible for its toxicity in humans?

Accepted Answer

Lipid A of lipopolysaccharide (LPS)

Question 7

A scientist is studying a bacterium with a cell wall composed of mycolic acid. Which staining technique should be used to identify this bacterium?

Accepted Answer

Acid-fast stain

Question 8

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

Accepted Answer

Their outer membrane acts as a barrier to many antibiotics.

Question 9

Which of the following is a function of bacterial fimbriae?

Accepted Answer

Attachment to surfaces

Question 10

A bacterium is observed to form chains of rod-shaped cells. What is the correct term for this arrangement?

Accepted Answer

Streptobacilli

Question 11

Which of the following best describes the chemical structure of peptidoglycan?

Accepted Answer

A polymer of N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM) linked by polypeptides

Question 12

Which of the following is NOT a function of the plasma membrane in prokaryotic cells?

Accepted Answer

Site of protein synthesis

Question 13

A bacterium is found to have a capsule, fimbriae, and pili. Which of the following is the most likely function of the pili?

Accepted Answer

Transfer of DNA between cells

Question 14

Which of the following best explains why alcohol decolorizes Gram-negative bacteria during the Gram stain procedure?

Accepted Answer

Alcohol dissolves the outer membrane and leaves holes in the thin peptidoglycan layer, allowing the dye to wash out.

Question 15

Which of the following arrangements describes a cubelike group of eight cocci?

Accepted Answer

Sarcinae

Question 16

Which of the following is a unique feature of Gram-positive cell walls?

Accepted Answer

Presence of teichoic acids

Question 17

A bacterium is identified as having a peritrichous arrangement of flagella. What does this mean?

Accepted Answer

It has flagella distributed over the entire cell surface.

Question 18

Which of the following best describes the role of porins in Gram-negative bacteria?

Accepted Answer

They form channels through the outer membrane for the passage of molecules.

Question 19

Which of the following is a real-world consequence of the presence of Lipid A in Gram-negative bacteria?

Accepted Answer

It acts as an endotoxin, contributing to septic shock in infected patients.

Question 20

Which of the following best explains why damage to the plasma membrane by alcohols or detergents can kill bacterial cells?

Accepted Answer

It causes leakage of cell contents due to loss of selective permeability.

Functional Anatomy of Prokaryotic and Eukaryotic Cells: Structure and Function

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