The diagram is a model of one way that materials move into a cell.

Which sentence explains what happens in the last step?

A vacuole carries particles into the cell.

B. Phospholipids in the cell membrane allow particles to pass through.

C. Transport proteins push particles out of the cell.

D. The cell membrane surrounds particles outside the cell.

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.

Consider an organism that is eukaryotic, found in both unicellular and multicellular forms, may resemble a plant but is not photosynthetic, has chitin in its cell walls, and absorbs organic nutrients from decomposing material in the environment. this organism would be classified as which of the following types of organisms? a. fungib. protozoac. bacteriad. archaea

As a small change in a person's dna can cause a genetic disorder