ATI RN
Questions on Immune System Questions
Question 1 of 5
What is the function of IgA in the intestine?
Correct Answer: C
Rationale: IgA binds microbes to block adhesion ; it doesn't inflame , produce cytokines , or SCFAs .
Question 2 of 5
Epithelial surfaces provide the first line of defense against infection by the use of several types of mechanisms. One of the chemical mechanisms used by epithelia is:
Correct Answer: B
Rationale: Antimicrobial peptides are chemical defenses; tight junctions are physical, mucus and cilia are mechanical.
Question 3 of 5
The drawing in Figure Q4.12 shows antibodies bound to repetitive epitopes on the surface of a bacterial pathogen. Even though all of these epitopes are identical, not all of them have antibodies bound to them. The most likely explanation for this failure of antibodies to bind to every possible epitope on the surface of the pathogen is:
Correct Answer: C
Rationale: Steric hindrance limits binding to all epitopes; insufficient antibody , evasion , or dual-site binding are less likely.
Question 4 of 5
eyeball too short cause
Correct Answer: A
Rationale: An eyeball that is too short causes farsightedness (hyperopia) because light focuses behind the retina, making near objects blurry.
Question 5 of 5
When you cut yourself, the damaged cells immediately release chemical alarm signals, such as
Correct Answer: C
Rationale: Histamine is released by damaged cells (e.g., mast cells) to initiate inflammation, unlike interferon (antiviral), complement (immune enhancement), or antihistamine (blocks histamine).