A) each cell maintains homeostasis at the cellular level.
B) cells are the smallest units that carry out the essential functions of life.
C) cells are the building blocks of all organisms.
D) all cells come from the division of preexisting cells.
E) every cell is capable of living on its own if isolated from the body.

A) a protein.
B) a cell.
C) a tissue.
D) an organ.
E) an organ system.

A) the nucleus
B) the nucleolus
C) the cytosol
D) the plasma membrane
E) the cytoskeleton