Question 1

Which of the following best distinguishes the innate immune response from the adaptive immune response?

Accepted Answer

The innate immune response is present at birth and acts immediately, while the adaptive response develops over time and is highly specific.

Question 2

Which of the following is NOT considered a first line of defense in the innate immune system?

Accepted Answer

Production of antibodies by B lymphocytes

Question 3

A patient with a genetic defect in the production of lysozyme would be most susceptible to which of the following?

Accepted Answer

Increased bacterial infections due to impaired breakdown of peptidoglycan in bacterial cell walls

Question 4

Which of the following best describes the role of normal flora in the first line of defense?

Accepted Answer

They compete with pathogens for nutrients and attachment sites, a process known as competitive exclusion.

Question 5

Which of the following blood components is correctly matched with its primary function?

Accepted Answer

Platelets: blood clotting

Question 6

Which of the following leukocytes is NOT considered a professional phagocytic cell?

Accepted Answer

Basophils

Question 7

Toll-like receptors (TLRs) play a crucial role in the innate immune response by:

Accepted Answer

Detecting conserved molecular patterns found on pathogens, such as lipopolysaccharides

Question 8

Which of the following best describes the sequence of events during phagocytosis?

Accepted Answer

Adherence → Ingestion → Formation of phagolysosome → Digestion → Exocytosis

Question 9

A bacterial pathogen produces a capsule that prevents binding of C3b. What is the most likely consequence for the host?

Accepted Answer

Reduced phagocytosis because C3b cannot act as an opsonin

Question 10

Which of the following is a correct statement about the inflammatory response?

Accepted Answer

Neutrophils are among the first cells to arrive at the site of injury due to chemotaxis.

Question 11

A patient presents with redness, heat, swelling, and pain at a wound site. These symptoms are primarily due to:

Accepted Answer

Vasodilation and increased permeability of blood vessels

Question 12

Which of the following best explains the role of IL-1 in the development of fever?

Accepted Answer

IL-1 acts as a pyrogen, signaling the hypothalamus to increase the body's temperature set point.

Question 13

Which of the following is a benefit of fever during infection?

Accepted Answer

It increases the rate of tissue repair and inhibits the growth of some pathogens.

Question 14

Interferons are most effective against which type of pathogen?

Accepted Answer

Viral pathogens

Question 15

Which of the following is NOT a function of the complement system?

Accepted Answer

Antibody production

Question 16

Which complement protein is primarily responsible for opsonization?

Accepted Answer

C3b

Question 17

A patient is unable to produce C5a. Which of the following immune functions would be most directly impaired?

Accepted Answer

Chemotaxis of phagocytic cells to the site of infection

Question 18

Which of the following statements about B and T lymphocytes is correct?

Accepted Answer

They are involved in the adaptive immune response and do not play a role in innate immunity.

Question 19

Which of the following is a correct pairing of complement activation pathway and its trigger?

Accepted Answer

Classical pathway: triggered by antigen-antibody complexes

Question 20

A patient with a severe burn loses a large area of skin. Which aspect of the innate immune system is most compromised?

Accepted Answer

Physical barrier to microbial entry

Innate Immunity: Nonspecific Defenses of the Host (Chapter 16) Study Guide

Study Guide - Practice Questions