Oddity/Factoid/Challenge questions

Question 1

Which pathway will not be initiated on the surface of mammalian cells?

Answer 1

the alternative pw

mammals have a regulatory protein that inhibits the activation of alternative pathway

Question 2

How is the C3Bb complex dismantled?

Answer 2

Decay accelerating factor (DAF), complement receptor 1 (CR1) and factor 1 dissociate the complement C3 convertase (C3bBb) from host cells

Question 3

Which pathway possesses a spontaneous amplification loop?

Answer 3

the alternative pathway

Question 4

Effector function of the Cxa’s and Cxb’s

Answer 4

C3a and C5a –> activate leukocytes, stimulating inflammation

C3b —-> opsonization for phags

C3b + proteins —> C5 convertase

C5b + C6, C7, C8, C9 —> MAC attack

Question 5

Which complement proteins cause contraction of smooth muscle?

Which complement proteins cause increased permeability of vessels?

Which complement proteins cause degrandulation of basophils?

Which complement proteins induce chemotaxis, release of 02 radicals and lysosomal enzymes?

Answer 5

C3a, C4a, C5a

C5a the most

C3a and C4a

C5a the most

all of them the same amount

only C5a