Question 1

Which of the following is a key structural difference between prokaryotic and eukaryotic cells?

Accepted Answer

Eukaryotic cells have a true nucleus enclosed by a membrane, while prokaryotic cells have a nucleoid region without a membrane.

Question 2

A bacterium is observed to be rod-shaped and forms chains. What is the correct term for this arrangement?

Accepted Answer

Streptobacilli

Question 3

Which structure allows bacteria to adhere to surfaces and is a major factor in the formation of biofilms?

Accepted Answer

Glycocalyx

Question 4

Which of the following best describes the function of bacterial flagella?

Accepted Answer

Motility by rotation

Question 5

A patient is diagnosed with a bacterial infection caused by a spirochete. Which structure is responsible for the corkscrew motility of this organism?

Accepted Answer

Axial filaments (endoflagella)

Question 6

Which of the following statements about Gram-positive and Gram-negative cell walls is correct?

Accepted Answer

Gram-positive bacteria have a thick peptidoglycan layer and no outer membrane.

Question 7

Why are antibiotics that target peptidoglycan synthesis, such as penicillin, generally ineffective against Mycoplasma species?

Accepted Answer

Mycoplasma species lack a cell wall and instead have sterols in their plasma membrane.

Question 8

Which of the following is a function of the bacterial capsule?

Accepted Answer

Prevents dehydration and loss of nutrients

Question 9

A Gram-negative bacterium is identified by the presence of which unique cell wall component?

Accepted Answer

Lipopolysaccharide (LPS)

Question 10

During Gram staining, why do Gram-positive bacteria retain the crystal violet stain?

Accepted Answer

Their thick peptidoglycan layer collapses and traps the crystal violet-iodine complex.

Question 11

Which of the following best explains why endospores are difficult to eliminate in clinical and food preparation settings?

Accepted Answer

Endospores are highly resistant to heat, desiccation, and chemicals.

Question 12

Which of the following is a correct description of a protoplast?

Accepted Answer

A wall-less cell derived from a Gram-positive bacterium

Question 13

A scientist is studying a bacterium that is oval-shaped and intermediate between cocci and bacilli. What is the correct term for this morphology?

Accepted Answer

Coccobacillus

Question 14

Which of the following is a distinguishing feature of acid-fast bacteria?

Accepted Answer

Presence of mycolic acid in the cell wall

Question 15

Which bacterial structure is primarily responsible for the transfer of genetic material between cells during conjugation?

Accepted Answer

Pili

Question 16

A patient is infected with a Gram-negative bacterium that causes a strong inflammatory response. Which component of the cell wall is most likely responsible for this effect?

Accepted Answer

Lipid A of lipopolysaccharide (LPS)

Question 17

Which of the following best describes the process of sporulation in bacteria?

Accepted Answer

A survival mechanism resulting in the formation of a highly resistant endospore

Question 18

Which of the following is true regarding the arrangement of bacterial flagella?

Accepted Answer

Lophotrichous bacteria have a tuft of flagella at one or both poles.

Question 19

Which of the following statements about archaea is correct?

Accepted Answer

Archaea may have cell walls made of pseudomurein, which lacks NAM and D-amino acids.

Question 20

A laboratory technician observes a bacterial sample that stains red after Gram staining. Which of the following best explains this result?

Accepted Answer

The bacterium has a thin peptidoglycan layer and an outer membrane, causing the primary stain to be washed out and the counterstain to be retained.

Functional Anatomy of Prokaryotic and Eukaryotic Cells: Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard