Question 1

Which of the following statements best describes the main structural difference between Gram-positive and Gram-negative bacteria as revealed by the Gram stain?

Accepted Answer

Gram-positive bacteria have a thick peptidoglycan layer and lack an outer membrane.

Question 2

A patient presents with a severe sore throat and is diagnosed with a Streptococcus infection. Which of the following features is most likely to contribute to the pathogenicity of Streptococcus species?

Accepted Answer

Production of a capsule that inhibits phagocytosis.

Question 3

Which of the following prokaryotes is known for producing antibiotics and has a filamentous structure similar to fungi?

Accepted Answer

Streptomyces

Question 4

Methanogens, halophiles, and thermophiles are all types of which group of microorganisms, and what is a unique feature of this group?

Accepted Answer

Archaea; they have unique membrane lipids and can survive extreme environments.

Question 5

Which of the following best describes the movement mechanism of spirochetes such as Treponema pallidum?

Accepted Answer

They move using axial filaments located between the cell wall and outer membrane.

Question 6

Which of the following is a distinguishing feature of eukaryotic cells compared to prokaryotic cells?

Accepted Answer

Presence of membrane-bound organelles such as the nucleus.

Question 7

A patient is diagnosed with malaria after returning from a trip to Africa. Which protist is responsible for this disease, and what is its vector?

Accepted Answer

Plasmodium; transmitted by Anopheles mosquitoes.

Question 8

Which of the following statements about fungi is correct?

Accepted Answer

Fungi have cell walls made of chitin and reproduce by forming spores.

Question 9

Which of the following is a correct pairing of a disease-causing protist and the disease it causes?

Accepted Answer

Trypanosoma – African sleeping sickness

Question 10

A patient is infected with a tapeworm. Which of the following statements about tapeworms is correct?

Accepted Answer

Tapeworms are flatworms that absorb nutrients through their skin and lack a digestive system.

Question 11

Which of the following best describes the lytic cycle of a bacteriophage?

Accepted Answer

The virus injects its DNA, replicates, assembles new viruses, and lyses the host cell to release progeny.

Question 12

Which of the following is a unique feature of enveloped viruses?

Accepted Answer

They acquire their envelope from the host cell membrane during budding.

Question 13

Which of the following viruses is classified as a retrovirus and is associated with the development of AIDS?

Accepted Answer

HIV

Question 14

A latent virus can remain dormant in a host cell for years before reactivating. Which of the following is an example of a disease caused by a latent virus?

Accepted Answer

Herpes simplex virus causing cold sores.

Question 15

Which of the following terms best describes a disease that is newly identified or increasing in incidence in the population?

Accepted Answer

Emerging

Question 16

Which of the following is a correct statement about prions?

Accepted Answer

Prions are infectious proteins that cause neurodegenerative diseases.

Question 17

A hospital outbreak of pneumonia is traced to a Gram-negative, rod-shaped bacterium that is resistant to many antibiotics and can form biofilms on medical equipment. Which organism is most likely responsible?

Accepted Answer

Pseudomonas aeruginosa

Question 18

Which of the following equations correctly represents the exponential growth of a bacterial population, where $$N_0 is $$the initial number of cells, $$n is $$the number of generations, and $$N is $$the final number of cells?

Accepted Answer

$$N = N_0$ 	imes 2^n$$

Question 19

Which of the following best explains the connection between viruses and cancer?

Accepted Answer

Some viruses can insert oncogenes or activate host oncogenes, leading to uncontrolled cell growth.

Question 20

A patient is diagnosed with West Nile virus. Which of the following is the most likely vector responsible for transmission of this virus?

Accepted Answer

Mosquitoes

Microbiology Study Guide: Prokaryotes, Eukaryotes, and Viruses (Chapters 11–13)

Study Guide - Practice Questions

Study Guide - Flashcards