Which statement is true about the main ingredient of a cell? a). The cytoplasm holds all the organelles in place
b).Water makes up more than 75 percent of a cell and surrounds the cell
c).The membrane-bound organelles make up all of the cell
d).The cell membrane encloses and protects the cell

What evidence is there that convection occurs in earth’s troposphere?

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.

Fredrick griffith made a scientific discovery in 1928