The Complement System

Question 1

The Complement System

Answer 1

It is the activity of blood serum that complete the action of antibodies.

Question 2

Complement proteins normally circulate as inactive
precursors :

Answer 2

(pro-proteins, proenzymes, zymogens )

Question 3

Complement proteins are generally

Answer 3

synthesized by the
liver hepatocytes, blood monocytes, tissue
macrophages, and epithelial cells of the genitourinal
tract and gastrointestinal tract

Question 4

Activation of complement

Answer 4

(removes an inhibitory fragment and exposes the active
site)

Question 5

The product of complement

Answer 5

activation become covalently
attached to microbial cell surfaces or to antibodies bound to microbes

Question 6

Complement activation is inhibited by

Answer 6

regulatory proteins that are present on normal host cells and absent from microbes.

Question 7

Classical

Answer 7

c1 c4 c2 c3 9 ca mg

Question 8

lectin

Answer 8

MBL MASP -1 & -2
C4 C3 C2 Mg

Question 9

Alternative:

Answer 9

B D C3 Mg

Question 10

Terminal

Answer 10

C5 C6 C7 C8 C9

Question 11

Lysis

Answer 11

the major effector of the
humoral branch of the immune system.

Question 12

Opsonization

Answer 12

which promotes phagocytosis of particulate Ags

Question 13

Immune clearance

Answer 13

which removes immune complexes from the circulation and deposits them in the spleen and liver

Question 14

Binding to specific complement receptors on cells of the immune system,

Answer 14

triggering specific cell functions, inflammation, and
secretion of immunoregulatory molecules

Question 15

Classical pathway

Answer 15

Ag Ab complex ( igG igM )

Question 16

lectin pathway

Answer 16

pathogen surface ( mannan on bacteria and viruses )

Question 17

Alternative pathway

Answer 17

pathogen surface ( LPS polymer CHO venom factor )

Question 18

Complement activation

Answer 18

1-Recruitment and activation of Inflammatory cells.
2-Opsonization of Pathogens and Immune complexes .
3-Killing of Pathogens e.g. lysis