Question 1

Which of the following best describes the main difference between the first and third lines of host defense?

Accepted Answer

The first line is innate and nonspecific, while the third line is acquired and specific, developing immunologic memory.

Question 2

A patient with a genetic mutation that prevents the production of lysozyme would be most susceptible to which of the following?

Accepted Answer

Increased risk of bacterial infections due to impaired hydrolysis of bacterial cell walls

Question 3

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

Accepted Answer

Transporting oxygen to tissues

Question 4

Which cell type is primarily responsible for the destruction of parasitic worms and mediating allergy?

Accepted Answer

Eosinophils

Question 5

A person with a deficiency in C3 protein would have a defect in which immune process?

Accepted Answer

Complement cascade activation

Question 6

Which of the following best explains why humans do not acquire distemper from cats?

Accepted Answer

Humans lack the genetic receptors required for the distemper virus to infect their cells.

Question 7

Which of the following is a correct sequence of events during the inflammatory response?

Accepted Answer

Injury → Vasoconstriction → Vasodilation → Edema → Scar formation

Question 8

Which of the following is a unique characteristic of leukocytes that allows them to migrate out of blood vessels into tissues?

Accepted Answer

Diapedesis

Question 9

Which of the following statements about interferons is TRUE?

Accepted Answer

Type II interferons are produced by T cells and NK cells and activate macrophages.

Question 10

A patient with a thymus that failed to develop properly would most likely have a deficiency in which cell type?

Accepted Answer

T cells

Question 11

Which of the following best describes the role of pattern recognition receptors (PRRs) on white blood cells?

Accepted Answer

They recognize pathogen-associated molecular patterns (PAMPs) to trigger immune responses.

Question 12

Which of the following is a function of the spleen in the immune system?

Accepted Answer

Filters circulating blood to remove worn out RBCs and pathogens

Question 13

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

Accepted Answer

Inhibits multiplication of temperature-sensitive microbes

Question 14

Which of the following best describes the process of phagocytosis?

Accepted Answer

A cell engulfs and digests foreign particles, microbes, or dead cells

Question 15

Which of the following is TRUE regarding the complement cascade?

Accepted Answer

It involves a series of enzymatic reactions that help destroy pathogens and promote inflammation.

Question 16

Which of the following is an example of a chemical barrier in the first line of defense?

Accepted Answer

Hydrochloric acid in the stomach

Question 17

Which of the following best explains why the third line of defense is considered 'adaptive'?

Accepted Answer

It develops in response to specific pathogens and creates immunologic memory.

Question 18

Which of the following is a correct pairing of a leukocyte and its primary function?

Accepted Answer

Neutrophil – Early response to bacteria and damaged tissue

Question 19

A patient with a mutation in the gene for interleukin-1 (IL-1) would most likely have which of the following symptoms reduced during infection?

Accepted Answer

Fever

Question 20

Which of the following is a function of dendritic cells in the immune system?

Accepted Answer

Trapping pathogens and presenting antigens to lymphocytes

Host Defenses and Innate Immunity: An Overview of the Immune System

Study Guide - Practice Questions