The are thin-walled blood vessels that exchange materials through their walls.

a. arteries
b. arterioles
c. capilleries
d. venules

scientists have discovered that hiv does not cause aids by the virus's direct effect on the host's immune cells, but rather through the cells' lethal influence on one another. researchers from the gladstone institutes have revealed that hiv does not cause aids by the virus's

the answer is b. glad to .

not always but somethings can be reproduced in a laboratory.

answer; the male's sperm cells have mitochondria, but because the sperm contributes dna but no cytoplasm, no mitochondria are passed to the egg at ferilization;