What are the structural differences between viruses and cells? Check all of them that apply. There is more than one. a) No organelles
b) No cell membrane
c) No nucleus
d) No DNA

Why are scientists concerned about the depletion of the ozone levels in the stratosphere?

Phosgene is a chemical agent that is formed by decomposition of chlorinated hydrocarbon solvents by ultraviolet radiation. a. false b. true

The frequency of alleles in a population that is in hardy weinberg equilibrium? a . changes in each successive generation b. is less important than the frequency genotypes c. shows evidence of the process of natural selection d. remains the same over several generations