Both single-celled and multicellular algae are found in the kingdom protista. consider the two examples seen here. the single-celled algae on the left is capable of independent living because

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.

Compare the composition of the moon's surface with the composition of the earth's surface.

Isotopes of the same element have differ in their