Question 1

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

Accepted Answer

The innate immune system responds quickly and is nonspecific, while the adaptive immune system is slower and highly specific.

Question 2

A patient presents with a bacterial infection. Which of the following is the first line of defense that the bacteria must overcome?

Accepted Answer

Surface barriers such as the keratinized epidermis and mucous membranes

Question 3

Which of the following is NOT a function of inflammation?

Accepted Answer

Directly produces antibodies to neutralize pathogens

Question 4

Which chemical mediator is primarily responsible for vasodilation during the inflammatory response?

Accepted Answer

Histamine

Question 5

A virus infects a cell and the cell begins to secrete interferons. What is the primary effect of these interferons on neighboring cells?

Accepted Answer

They stimulate neighboring cells to produce antiviral proteins that block viral reproduction.

Question 6

Which of the following best describes the process of opsonization?

Accepted Answer

The coating of pathogens with molecules that enhance phagocytosis

Question 7

Which cell type is most abundant in the blood and is the first to arrive at the site of infection during inflammation?

Accepted Answer

Neutrophils

Question 8

A patient with a high fever is at risk for which of the following complications?

Accepted Answer

Inactivation of enzymes and body proteins required for defense

Question 9

Which of the following is a correct sequence of events in phagocyte mobilization during inflammation?

Accepted Answer

Leukocytosis → Margination → Diapedesis → Chemotaxis

Question 10

Which of the following best explains why natural killer (NK) cells can target cancer cells?

Accepted Answer

NK cells recognize cells lacking 'self' cell surface receptors and induce apoptosis.

Question 11

Which of the following is a function of complement proteins in the immune response?

Accepted Answer

Enhancing inflammation, opsonization, and cell lysis

Question 12

A patient develops an abscess after a bacterial infection. What is the primary composition of pus in this abscess?

Accepted Answer

Dead and dying neutrophils, broken-down tissue cells, and living and dead pathogens

Question 13

Which of the following is a cardinal sign of inflammation and its physiological cause?

Accepted Answer

Redness caused by vasodilation and increased blood flow (hyperemia)

Question 14

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

Accepted Answer

They recognize pathogen-associated molecular patterns and trigger the release of cytokines that promote inflammation.

Question 15

Which of the following antimicrobial proteins is most directly involved in blocking viral replication in neighboring cells?

Accepted Answer

Interferon

Question 16

A bacterial pathogen is resistant to lysosomal enzymes. Which mechanism allows phagocytes to destroy such pathogens?

Accepted Answer

Respiratory burst, which releases cell-killing free radicals and oxidizing chemicals

Question 17

Which of the following is a real-life example of the adaptive immune system in action?

Accepted Answer

Production of specific antibodies after vaccination against a virus

Question 18

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

Accepted Answer

It causes the liver and spleen to sequester iron and zinc, which bacteria need to multiply.

Question 19

Which of the following is a correct description of the role of defensins in innate immunity?

Accepted Answer

They are antimicrobial peptides found in mucous membranes and skin that help destroy pathogens.

Question 20

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

Accepted Answer

Increased susceptibility to bacterial infections due to impaired cell lysis and opsonization

Innate Defenses of the Immune System: ANP Study Notes

Study Guide - Practice Questions