Question 1

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

Accepted Answer

Innate immunity uses germline-encoded receptors, while adaptive immunity uses variable antigen-specific receptors generated by gene rearrangement.

Question 2

Which of the following is NOT a function of complement proteins in the immune response?

Accepted Answer

Direct antibody production

Question 3

A patient with a genetic defect in the formation of the membrane attack complex (MAC) would most likely have increased susceptibility to which of the following?

Accepted Answer

Bacterial infections due to inability to lyse pathogens

Question 4

Which of the following best explains why normal flora are considered part of the first line of defense?

Accepted Answer

They outcompete pathogens for resources and alter local conditions to inhibit pathogen survival.

Question 5

Which of the following secretions contains lysozyme and contributes to the destruction of bacterial cell walls?

Accepted Answer

Sweat, tears, and saliva

Question 6

A patient is infected with Bordetella pertussis, which impairs ciliary action in the respiratory tract. Which first line of defense is most compromised?

Accepted Answer

Movement of bodily fluids and ciliary escalator

Question 7

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

Accepted Answer

Chemotaxis → Adherence → Ingestion → Digestion

Question 8

Which of the following is a mechanism by which some bacteria evade the complement system?

Accepted Answer

Forming capsules that prevent complement activation

Question 9

Which cell type is primarily responsible for the rapid phagocytosis of bacteria during the early stages of infection?

Accepted Answer

Neutrophils

Question 10

Which of the following best describes the role of interferon alpha ($$\alpha) $$and beta ($$\beta) in $$viral infections?

Accepted Answer

They stimulate the production of antiviral proteins in neighboring cells.

Question 11

A patient presents with a fever following a bacterial infection. Which of the following best explains the physiological benefit of fever in this context?

Accepted Answer

Fever increases the rate of chemical reactions and inhibits the growth of some microbes.

Question 12

Which of the following symptoms of inflammation is primarily caused by increased blood flow to the affected area?

Accepted Answer

Redness (rubor)

Question 13

Which of the following is NOT a characteristic of natural killer (NK) cells?

Accepted Answer

They require prior exposure to a specific antigen to function.

Question 14

Which of the following best describes the process of opsonization?

Accepted Answer

Complement proteins bind to the surface of microbes, enhancing their recognition and ingestion by phagocytes.

Question 15

A patient with a Mycobacterium infection is found to have bacteria surviving inside phagocytes. Which property of Mycobacterium allows this?

Accepted Answer

Thick, waxy capsule that resists digestion

Question 16

Which of the following is a chemical factor in the first line of defense that inhibits fungal growth on the skin?

Accepted Answer

Fungistatic fatty acids in sebum

Question 17

Which of the following best explains why inflammation is considered a nonspecific defense mechanism?

Accepted Answer

It is activated by a wide variety of injuries or infections, regardless of the specific pathogen.

Question 18

Which of the following is the correct formula for calculating the rate of a chemical reaction, such as those increased during fever?

Accepted Answer

$$k = Ae$$^{-E_a/(RT)}$$

Question 19

Which of the following is a direct result of prostaglandin release during fever?

Accepted Answer

Resetting of the hypothalamic thermostat to a higher temperature

Question 20

Which of the following best describes the role of chemotaxis in the immune response?

Accepted Answer

It is the process by which phagocytes are attracted to the site of infection by chemical signals.

Innate Immunity and Nonspecific Defenses: Mini-Textbook Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards