ATI RN
Lymphatic System Exam Questions Questions
Question 1 of 5
Which protein is involved in the lectin activation pathway and is made in the liver?
Correct Answer: A
Rationale: MASP (mannose-binding lectin-associated serine protease) activates the lectin pathway and is liver-made ; MCP, DAF, CD59 regulate complement.
Question 2 of 5
Which cells in the thymus are responsible for expressing tissue-specific antigens through the action of AIRE?
Correct Answer: A
Rationale: Medullary thymic epithelial cells express tissue-specific antigens via AIRE for negative selection.
Question 3 of 5
Vaccines generally confer what type of immunity?
Correct Answer: B
Rationale: Vaccines stimulate active immunity artificially ; passive (A, C) involves antibody transfer, natural active is from infection.
Question 4 of 5
Naive B and T lymphocytes are small, quiescent cells with little cytoplasm and low metabolic activity. Yet within hours after being activated following encounter with their antigen, these cells enlarge and up-regulate many biosynthetic and metabolic pathways. Approximately one day later, the cells begin dividing, and for several days they are the most rapidly dividing cells in the body, undergoing 2-4 rounds of cell division every day. In order to maintain this phenomenal rate of cell division, lymphoblasts must:
Correct Answer: C
Rationale: Lymphoblasts up-regulate glycolysis via glucose transporters/enzymes ; naive cells lack stores , don't engulf lymphocytes , or phagocytose broadly .
Question 5 of 5
Immunodeficiency diseases occur when individuals have defects in leukocyte adhesion to inflamed endothelial cells, thereby impeding the extravasation of phagocytes into infected tissues. When neutrophils from one class of these patients were isolated and tested using in vitro assays for neutrophil-endothelial cell interactions and extravasation, it was found that the neutrophils could slowly roll along the endothelial vessel wall but were unable to arrest and migrate across the endothelium. The most likely protein deficient in these neutrophils is:
Correct Answer: D
Rationale: Integrins mediate neutrophil arrest; rolling (selectins, B/C) occurs, but without integrins, migration fails; ICAMs are on endothelium.