In a large city experiencing urban blight, we would be surprised to find

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.

Give the biological term for: structures that display characteristics of living organisms only within living cells

Development of new communities in disturbed environments, such as a burned or a clear cut forest, is called