How do owls and hawks coexist and live in the same niche

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 membrane that sheath of schwann cell containing cytoplasm and nucleus that encloses myelin

Astudent measured the amount of carbon dioxide (co2) produced by yeast during an experiment. use the data in the table at the right to answer the questions below. which variable is the dependent variable?