Question 1

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

Accepted Answer

Innate immunity provides immediate, nonspecific defense, while adaptive immunity develops specific responses and memory after exposure.

Question 2

Which of the following is NOT a component of the body's first line of defense against infection?

Accepted Answer

Phagocytic cells

Question 3

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

Accepted Answer

Bacterial infections due to impaired destruction of bacterial cell walls

Question 4

Which of the following best explains the role of the microbiome in innate immunity?

Accepted Answer

It competes with pathogens for nutrients and attachment sites, and produces antimicrobial compounds.

Question 5

Which of the following cells is classified as an agranulocyte and is primarily responsible for phagocytosis in tissues?

Accepted Answer

Monocyte/Macrophage

Question 6

During the process of phagocytosis, what is the correct sequence of events?

Accepted Answer

Chemotaxis → Adhesion → Ingestion → Maturation → Killing → Elimination

Question 7

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

Accepted Answer

They secrete toxins onto the surface of virally infected cells and tumor cells.

Question 8

A patient presents with chronic inflammation. Which of the following is a likely consequence if this condition persists?

Accepted Answer

Increased risk of tissue damage and disease

Question 9

Which of the following statements about fever is correct?

Accepted Answer

Fever is triggered by pyrogens that reset the hypothalamic thermostat to a higher temperature.

Question 10

Which of the following best describes the function of complement proteins in innate immunity?

Accepted Answer

They form membrane attack complexes that lyse pathogens and enhance phagocytosis.

Question 11

A laboratory test shows a patient has an abnormally high percentage of neutrophils. What does this most likely indicate?

Accepted Answer

A bacterial infection

Question 12

Which of the following is a chemical defense found in both skin and mucous membranes that acts against a variety of microbes?

Accepted Answer

Antimicrobial peptides

Question 13

Which of the following is a correct pairing of a granulocyte with its primary function?

Accepted Answer

Eosinophil – defense against parasitic helminths

Question 14

Which of the following best explains why the skin is an effective barrier to infection?

Accepted Answer

It contains multiple layers of tightly packed cells, antimicrobial peptides, and a low pH.

Question 15

Which of the following is NOT a function of inflammation?

Accepted Answer

Production of antibodies

Question 16

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

Accepted Answer

They recognize pathogen-associated molecular patterns and trigger immune responses.

Question 17

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

Accepted Answer

Increased susceptibility to bacterial infections due to impaired lysis and opsonization

Question 18

Which of the following is a correct statement about the difference between granulocytes and agranulocytes?

Accepted Answer

Granulocytes have visible granules in their cytoplasm, while agranulocytes do not.

Question 19

Which of the following best describes the process by which phagocytes are attracted to the site of infection?

Accepted Answer

Chemotaxis

Question 20

Which of the following is a real-life example of microbial antagonism?

Accepted Answer

Normal gut bacteria outcompete Clostridioides difficile, preventing infection.

Innate Immunity: The Body’s First and Second Lines of Defense

Study Guide - Practice Questions