Choose a scientific theory and describe the theory.

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.

The earth's polarity has switched many times through history as evidence by what wh the earth clorets he has switched many times throughout history as evidence by what

Both male and female gametes are created during the process of meiosis. the formation of male gametes is called spermatogenesis. after telophase il of spermatogenesis, there would be are all genetically male gametes created that