Question 1

Which of the following correctly lists the stages of infection and disease in order?

Accepted Answer

Incubation, prodromal, illness, decline, convalescence

Question 2

A patient presents with a fever and a rash. Which of the following best describes these findings?

Accepted Answer

Fever is a sign; rash is a sign

Question 3

Which of the following scenarios best illustrates mutualism?

Accepted Answer

Bacteria in the human gut produce vitamin K, which benefits the host, while the bacteria receive nutrients and a stable environment.

Question 4

Which of the following best describes the difference between contamination, infection, and disease?

Accepted Answer

Contamination is the presence of microbes, infection is their successful invasion, and disease is the result of tissue damage or dysfunction.

Question 5

A disease that occurs at a relatively constant rate within a population is best described as:

Accepted Answer

Endemic

Question 6

Which of the following is NOT one of Koch's postulates?

Accepted Answer

The pathogen must be able to be treated with antibiotics.

Question 7

Which of the following best describes the function of MHC class I molecules?

Accepted Answer

They present endogenous antigens to cytotoxic T cells.

Question 8

A patient is bitten by a mosquito carrying malaria. What is the mode of transmission in this case?

Accepted Answer

Vector transmission

Question 9

Which of the following statements about exotoxins and endotoxins is correct?

Accepted Answer

Exotoxins are secreted proteins, while endotoxins are part of the outer membrane of Gram-negative bacteria.

Question 10

Which of the following best describes the process of opsonization?

Accepted Answer

Antibodies coat a pathogen, enhancing its uptake by phagocytes.

Question 11

Which of the following is a function of helper T cells?

Accepted Answer

They activate B cells and cytotoxic T cells by releasing cytokines.

Question 12

Which antibody class is primarily responsible for the secondary immune response and is the most abundant in serum?

Accepted Answer

IgG

Question 13

A patient receives a vaccine and later is exposed to the pathogen. Which immune response is faster and more robust, and why?

Accepted Answer

Secondary immune response, due to memory B and T cells generated during the primary response.

Question 14

Which of the following best describes the role of antigen-presenting cells (APCs)?

Accepted Answer

They process and present antigens on MHC molecules to T cells.

Question 15

Which of the following is a characteristic of innate immunity?

Accepted Answer

It provides a rapid, non-specific response to pathogens.

Question 16

Which of the following best describes clonal selection?

Accepted Answer

The process by which lymphocytes with receptors specific to an antigen are activated and proliferate.

Question 17

A patient develops a fever after a bacterial infection. Which of the following best explains the physiological benefit of fever?

Accepted Answer

Fever increases the activity of immune cells and inhibits the growth of some pathogens.

Question 18

Which of the following best describes the function of regulatory T cells?

Accepted Answer

They suppress immune responses to prevent autoimmunity.

Question 19

Which of the following is a correct statement about cytokines?

Accepted Answer

Cytokines are signaling proteins that mediate and regulate immunity, inflammation, and hematopoiesis.

Question 20

A laboratory technician is exposed to a bloodborne pathogen via a needlestick injury. Which mode of transmission does this represent?

Accepted Answer

Vehicle transmission

Microbiology Study Guide: Infection, Immunity, and Adaptive Responses

Study Guide - Practice Questions