Which is an ion found in a glass of water?
A.) N+
B.) O2
C.) H+
D.) O-

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.

Which statement is true about the cell theory? a) it is well-supported by evidence. b) it is unchangeable and permanent.

Which material is commonly used as a culture medium for living cells