Which of the following represents an abiotic factor? O Bacteria
O Protist
O Plants
Wind

What happens when a magniseum ion ia atracked to a chlrene ion

Which of the following is a possible reason for sleep? a) growth b)digestive c)speed d)intelligence

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.