Where can most of the fresh water on the earth be found

The gene that causes sickle-cell disease is present in a higher percentage of residents of sub-saharan africa than among those of african descent living in the united states. even though this gene causes sickle-cell disease, it also provides some protection from malaria, a serious disease that is widespread in sub-saharan africa but absent in the united states. discuss an evolutionary process that could account for the different percentages of the sickle-cell gene among residents of the two regions.

Which worm has eyespots that are used to detect light? a fluke b marine worm c planarian d tapeworm

How and why organisms are hierarchically classifies