The Cell Membrane is semipermeable, therefore: The cell is surrounded by plasma , the nucleus is in the middle of all cells .The nucleus also controls every cell , but not just one nucleus , every cell has its own job there are no copies , when you have cells that do what the other is doing you will have an condition called down syndrome.
: ANSWER= Plasma surrounds the cell. NOT all things can enter & leave the cell , This property helps the cell maintain homeostasis.
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