Question 1

Which of the following best defines a bacterial strain?

Accepted Answer

A population of bacteria that descend from a single cell and have identical genetic makeup.

Question 2

Which of the following structures is present in ALL types of cells (prokaryotic and eukaryotic)?

Accepted Answer

Plasma membrane

Question 3

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

Accepted Answer

Glycocalyx (capsule)

Question 4

Which of the following best describes the difference between Gram-positive and Gram-negative bacterial cell walls?

Accepted Answer

Gram-positive bacteria have a thick peptidoglycan layer and teichoic acids, while Gram-negative bacteria have a thin peptidoglycan layer and an outer membrane containing lipopolysaccharide.

Question 5

Which group of bacteria possesses axial filaments, and how does this structure affect their movement?

Accepted Answer

Spirochetes; axial filaments allow corkscrew-like motility through viscous environments.

Question 6

A laboratory technician is using a Gram stain to differentiate bacteria. Which step in the process is responsible for decolorizing Gram-negative cells?

Accepted Answer

Alcohol (ethanol or acetone) wash

Question 7

Which of the following statements about endospores is TRUE?

Accepted Answer

Endospores are produced by genera such as Bacillus and Clostridium and are highly resistant to heat and chemicals.

Question 8

Which of the following best explains why Mycoplasma species are unique among bacteria?

Accepted Answer

They lack a cell wall entirely and have sterols in their plasma membrane.

Question 9

A scientist discovers a eukaryotic microorganism with a cell wall made of cellulose. To which kingdom does this organism most likely belong?

Accepted Answer

Algae

Question 10

Which of the following statements correctly compares prokaryotic and eukaryotic flagella?

Accepted Answer

Eukaryotic flagella are composed of microtubules and move in a whip-like fashion, while prokaryotic flagella are made of flagellin and rotate like a propeller.

Question 11

Which of the following is a function of bacterial plasmids?

Accepted Answer

They often carry genes for antibiotic resistance or virulence factors.

Question 12

A patient is diagnosed with a mycosis. What does this term refer to?

Accepted Answer

A fungal infection in the body

Question 13

Which of the following best describes the difference between asexual and sexual spores in fungi?

Accepted Answer

Asexual spores are produced by budding or mitosis, while sexual spores are formed after the fusion of two nuclei and meiosis.

Question 14

Which of the following statements about protozoa is correct?

Accepted Answer

Protozoa are classified into groups based on their means of locomotion.

Question 15

A patient is infected with a helminth that requires two different hosts to complete its life cycle. The host in which sexual reproduction occurs is called the:

Accepted Answer

Definitive host

Question 16

Which of the following statements about viruses is TRUE?

Accepted Answer

Viruses are acellular and require a host cell for replication.

Question 17

Which of the following best explains why RNA viruses evolve faster than DNA viruses?

Accepted Answer

RNA viruses have higher mutation rates due to lack of proofreading during replication.

Question 18

A hospital experiences an outbreak of influenza. Genetic analysis reveals a major change in the viral genome due to reassortment of gene segments from two different strains. This is an example of:

Accepted Answer

Antigenic shift

Question 19

Which of the following best describes the process of phage conversion?

Accepted Answer

A bacterium acquires new genetic traits due to the integration of a prophage.

Question 20

Which of the following is a key feature of prions?

Accepted Answer

They are infectious proteins that cause neurodegenerative diseases.

Comprehensive Study Notes: Prokaryotic and Eukaryotic Cells, Viruses, and Prions

Study Guide - Practice Questions

Study Guide - Flashcards