Question 1

Which of the following is a primary function of neutrophils in innate immunity?

Accepted Answer

Phagocytize bacteria and fungi

Question 2

A patient presents with a low white blood cell count. Which of the following conditions is most likely associated with this finding?

Accepted Answer

Viral infection

Question 3

Which physical factor of the skin contributes to its role as a barrier in innate immunity?

Accepted Answer

Shedding and dryness of the epidermis

Question 4

What is the main function of Toll-like receptors (TLRs) in the innate immune response?

Accepted Answer

Recognize pathogen-associated molecular patterns (PAMPs) and induce cytokine release

Question 5

Which chemical factor found in sweat, tears, saliva, and urine destroys bacterial cell walls?

Accepted Answer

Lysozyme

Question 6

A patient with a deficiency in C3 complement protein would most likely experience which of the following?

Accepted Answer

Susceptibility to bacterial infections

Question 7

Which of the following best describes the process of opsonization?

Accepted Answer

Coating of a microorganism with serum proteins to enhance phagocytosis

Question 8

Which of the following is NOT a function of inflammation?

Accepted Answer

Producing antibodies against pathogens

Question 9

Which stage of phagocytosis involves the chemical attraction of phagocytes to microorganisms?

Accepted Answer

Chemotaxis

Question 10

Which of the following statements about normal microbiota is TRUE?

Accepted Answer

They compete with pathogens for space and nutrients

Question 11

Which of the following is a chemical factor that inhibits microbial growth on the skin?

Accepted Answer

Sebum

Question 12

Which of the following leukocytes is primarily responsible for killing parasites and helminths?

Accepted Answer

Eosinophils

Question 13

Which process allows phagocytes to squeeze between endothelial cells of blood vessels to reach damaged tissue?

Accepted Answer

Diapedesis

Question 14

Which of the following is a consequence of complement activation?

Accepted Answer

Cytolysis of pathogens

Question 15

Which of the following best describes the role of interferons (IFN α and IFN β) in viral infections?

Accepted Answer

They cause neighboring cells to produce antiviral proteins

Question 16

Which iron-binding protein is found in blood and tissue fluids and helps deprive pathogens of iron?

Accepted Answer

Transferrin

Question 17

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

Accepted Answer

Lactobacillus in the vagina producing H2O2 to inhibit Chlamydia

Question 18

Which of the following is a multi-step process that involves both innate and adaptive immunity?

Accepted Answer

Activation of complement via the classical pathway

Question 19

Which of the following is a function of acute-phase proteins released during inflammation?

Accepted Answer

Increase permeability of blood vessels

Question 20

Which of the following best explains why scientists are interested in antimicrobial peptides (AMPs)?

Accepted Answer

AMPs are short peptides that inhibit cell wall synthesis and destroy DNA/RNA, offering broad-spectrum antimicrobial activity

16 Innate Immunity: Nonspecific Defenses of the Host

Study Guide - Practice Questions