Question 1

Which of the following best describes the role of Toll-like receptors (TLRs) in the innate immune system?

Accepted Answer

They recognize specific-shaped molecules on pathogens and trigger an immune response.

Question 2

A patient receives a deep cut on their leg, which becomes red, swollen, and painful. Which process is primarily responsible for these symptoms?

Accepted Answer

Inflammation

Question 3

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

Accepted Answer

Production of antibodies by B cells

Question 4

A person inhales airborne Mycobacterium tuberculosis. Which line of defense is first breached?

Accepted Answer

First line: mucous membranes

Question 5

Which of the following best explains why fever can be beneficial during infection?

Accepted Answer

It inhibits the growth of some pathogens and enhances immune reactions.

Question 6

Which of the following is an example of opsonization?

Accepted Answer

Antibodies or complement proteins coat a pathogen, enhancing phagocytosis.

Question 7

Which of the following is a correct sequence of events in phagocytosis?

Accepted Answer

Adherence → Engulfment → Formation of phagolysosome → Digestion

Question 8

A person with a genetic defect in complement proteins would most likely experience which of the following?

Accepted Answer

Impaired ability to lyse bacteria and amplify inflammation

Question 9

Which of the following best describes the difference between innate and adaptive immunity?

Accepted Answer

Innate immunity provides immediate, nonspecific defense; adaptive immunity is specific and has memory.

Question 10

A patient with a bacterial infection has pus at the site of injury. What does the presence of pus indicate?

Accepted Answer

Mixture of dead neutrophils, tissue cells, and pathogens

Question 11

Which of the following is a function of natural killer (NK) cells?

Accepted Answer

They kill virus-infected and cancer cells by inducing apoptosis.

Question 12

Which of the following is a cardinal sign of inflammation caused by increased blood flow to the affected area?

Accepted Answer

Redness

Question 13

Which of the following best describes the process of chemotaxis during inflammation?

Accepted Answer

Phagocytes are attracted to the site of injury by chemical signals.

Question 14

Which of the following is a real-life example of the chain of infection being broken at the 'portal of entry'?

Accepted Answer

Wearing gloves to prevent pathogens from entering a cut on the hand

Question 15

Which of the following best explains why the skin is considered a mechanical barrier in the immune system?

Accepted Answer

It forms a continuous layer that prevents entry of pathogens.

Question 16

A person with a deficiency in helper T cells would most likely have problems with which aspect of immunity?

Accepted Answer

Activation of both B cells and cytotoxic T cells

Question 17

Which of the following is a correct description of the role of interferons?

Accepted Answer

They stimulate the production of proteins that inhibit viral replication in neighboring cells.

Question 18

Which of the following best describes the process of agglutination in humoral immunity?

Accepted Answer

Antibodies bind to multiple antigens, causing them to clump together.

Question 19

Which of the following is a function of cytotoxic T cells in the adaptive immune response?

Accepted Answer

They directly kill infected or cancerous cells by releasing perforin.

Question 20

A person receives a transfusion of mismatched blood. Which immune mechanism is most likely to occur?

Accepted Answer

Agglutination of donor red blood cells by recipient antibodies

Chapter 21: Immune System

Study Guide - Practice Questions