Question 1

A patient presents with sudden hypotension, hives, and throat swelling after exposure to peanuts. Which of the following is the most appropriate immediate treatment?

Accepted Answer

Inject epinephrine intramuscularly

Question 2

Which antibody is primarily involved in type I hypersensitivity reactions, such as anaphylaxis, and may be measured in serum during diagnosis?

Accepted Answer

IgE

Question 3

A woman with Rh− blood type is pregnant with an Rh+ fetus. What is the purpose of administering RhoGAM during pregnancy and after delivery?

Accepted Answer

To prevent the mother from producing anti-Rh antibodies

Question 4

Which of the following best describes the mechanism of action for interferons produced by virus-infected cells?

Accepted Answer

They stimulate nearby cells to reduce transcription and translation

Question 5

A patient with myasthenia gravis experiences severe muscle weakness. Which of the following best explains the underlying cause?

Accepted Answer

Antibodies target acetylcholine receptors at the neuromuscular junction

Question 6

Which of the following is NOT a function of antibodies?

Accepted Answer

Directly lysing bacteria via enzymatic activity

Question 7

A patient receives a blood transfusion with the wrong ABO blood type. Which of the following symptoms is most likely to occur first?

Accepted Answer

Hypotension

Question 8

Which of the following statements about the skin as a barrier is correct?

Accepted Answer

Dryness and acidity of the skin inhibit microbial growth

Question 9

Clostridium difficile is a rod-shaped, gram-positive, obligate anaerobe that can cause colitis. Which treatment is most effective for restoring normal colon microbiota?

Accepted Answer

Fecal transplant

Question 10

Which of the following best describes the role of the microbiome as an innate immune barrier?

Accepted Answer

It competes with pathogens for colonization sites and nutrients

Question 11

During the innate immune response to a wound infection, which sequence of events is correct?

Accepted Answer

Vasoconstriction → mast cell histamine release → leukocyte diapedesis → phagocytosis

Question 12

Which of the following is a characteristic of the adaptive immune system?

Accepted Answer

It has memory and specificity for previously encountered pathogens

Question 13

A patient develops colitis after antibiotic treatment. Which pathogen is most likely responsible, and what is the mechanism?

Accepted Answer

Clostridium difficile; overgrowth due to loss of normal microbiota

Question 14

Which process allows leukocytes to exit blood vessels and migrate toward a wound site?

Accepted Answer

Diapedesis

Question 15

Which of the following is a virulence factor?

Accepted Answer

Bacterial toxins

Question 16

Why must the influenza vaccine be administered annually?

Accepted Answer

Because the virus undergoes antigenic drift and shift, altering its surface proteins

Question 17

Which of the following equations best represents codominance in the ABO blood group system?

Accepted Answer

$$	ext{Genotype: IAIB} ightarrow 	ext{Phenotype: AB}$$

Question 18

A patient with Graves disease produces antibodies that mimic which hormone, leading to hyperthyroidism?

Accepted Answer

Thyroid-stimulating hormone (TSH)

Question 19

Which of the following best describes an opportunistic pathogen?

Accepted Answer

A pathogen that causes disease when host immunity is compromised

Question 20

Which antibody function involves the binding of multiple pathogens together, facilitating their removal?

Accepted Answer

Agglutination

Immune System Disorders, Blood Groups, and Host Defense Mechanisms

Study Guide - Practice Questions

Study Guide - Flashcards