Which of the following acts as an opsonin?
Correct Answer: C3b
Description: ANSWER: (B) C3bREF: Robbins 8th ed p. 59See previous question for figure of complement systemsThe following are the basic functions of the complementOpsonization - enhancing phagocytosis of antigensChemotaxis - attracting macrophages and neutrophilsLysis - rupturing membranes of foreign cellsClumping of antigen-bearing agents"The process of coating a particle such as a microbe, to target it for phagocytosis, is called opsonization, and substances that do it are called opsonins"Major opsonins: C3b, IgG, mannose binding lecithin (MBL), fibronectin, fibrinogen and CRP.Membrane attack complex: MAC has a subunit composition of C5b, C6, C7, C8, and polymeric C9Anaphylatoxin: Both C3a and C5a have anaphylatoxin activity
Category:
Microbiology
Get More
Subject Mock Tests
Practice with over 200,000 questions from various medical subjects and improve your knowledge.
Attempt a mock test nowMock Exam
Take an exam with 100 random questions selected from all subjects to test your knowledge.
Coming SoonGet More
Subject Mock Tests
Try practicing mock tests with over 200,000 questions from various medical subjects.
Attempt a mock test now