What causes the characteristic thrashing motion of nematodes?
A. the fluid-filled body cavity
B. the pseudocoelom that acts as a hydroskeleton
C. the blunted head and pointed tail

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