a) Dammage to the lining of a blood vessel

b) Exposure of blood to the air

c) Conversion of fibrinogen to fibrin

d) Attraction of Leukocytes to a site of infection

e) Conversion of fibrin to fibrinogen

a) Cut the number of species to the few survivors left today

b) Resulted mainly from the separation of the continents

c) Occurred regularly, about every million years

d) Were followed by diversification of the survivors

e) Wiped out land animals but had little effect on marine life

a) 3

b) 6

c) 12

d) 24

e) 48