ATI RN
Immune System Practice Questions Questions
Question 1 of 5
Select the statement that is true about the spleen
Correct Answer: D
Rationale: The spleen filters blood, not lymph ; lymph nodes filter lymph (A reversed), eosinophils aren't spleen-specific, and adult blood production is in bone marrow.
Question 2 of 5
B cells express a complement receptor that binds to C3b cleavage products, such as iC3b and C3dg. When a B cell with an antigen receptor that specifically recognizes that pathogen also has its complement receptor stimulated because the pathogen is opsonized with these C3 fragments, B cell activation is greatly enhanced. This mechanism functions to:
Correct Answer: A
Rationale: Complement enhances B-cell detection of pathogens early ; not prevention , phagocytosis , or just replication .
Question 3 of 5
Antibodies that bind with high affinity to some viral surface proteins require heavy chain CDR3 loops of unusual length. Whereas the average human heavy chain CDR3 length is ~15 amino acids, antibodies with V_H CDR3 loops of >30 amino acids are readily detected in the repertoire. These antibody heavy chains with CDR3 lengths of >30 amino acids would likely be missing in individuals lacking:
Correct Answer: D
Rationale: TdT adds nucleotides for long CDR3; RAG , DNA-PK , Artemis , and Ku are recombination essentials.
Question 4 of 5
Cardiac output
Correct Answer: D
Rationale: Cardiac output is defined as the volume of blood pumped by the heart per minute into the systemic circulation.
Question 5 of 5
Which of the following diseases cannot currently be prevented by vaccination?
Correct Answer: A
Rationale: As of 2012 (document date), no effective AIDS vaccine existed, unlike for polio, measles, and tetanus.