Complement System Table

Question 1

Initiation of the classical pathway by binding Ig

Answer 1

C1 (C1q)

Question 2

Serine protease. With C4b, is a C3 convertase

Answer 2

C2 (C2a)

Question 3

Inactive in complement pathway, Cleavage of C2b by plasmin releasees C@ kinin, a peptide that stimulates vasodilation

Answer 3

C2b

Question 4

Anaphylatoxin. Mediate inflammatory signals via C3aR

Answer 4

C3 (C3a)

Question 5

Potent in opsonization, tagging immune complexes, pathogens, and apoptopic cells for phagocytosis

Answer 5

C3b

Question 6

Proteolytic fragment of iC3b generated by factor I and trypsin-like proteases. binds CRIg on fixed tissue macrophages

Answer 6

C3c

Question 7

Anaphylatoxin,; binding to C5aR induces inflammation

Answer 7

C5 (C5a)

Question 8

Component of membrane attack complex (MAC). Binds cell membrane and facilitates binding of other components of the MAC

Answer 8

C5b

Question 9

Component of MAC. Stabilizes C5b. In the absence of C6, C5b is rapidly degraded

Answer 9

C6

Question 10

Component of MAC. Binds C5C6 and induces conformational change allowing C7 to insert into interior of membrane

Answer 10

C7

Question 11

Component of MAc. Binds C5C6C7 and creates a small pore in membrane

Answer 11

C8

Question 12

Component of MAC. Ten to 19 molecules of C9 bind C5C6C7C8 and create a large pore in membrane

Answer 12

C9