Consider the genetic cross for sex in humans xx is female and xy is male a family has four children all girls

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.

What is the following best defines climate?

Match the functions to the cell types ? contraction and relaxation. conducting electrochemical signals fighting diseases carrying genetic material