The cell membrane, which is usually semi-permeable.
the cell membrane controls what goes in and out the cell
IT CONTROLS WHAT GOES IN AND OUT OF THE CELL
Cell membrane
It controls what goes in and out of a cell.
it controls what goes in and out of the cell.
It controls what goes in and out of the cell.
cell membrane
cell membrane
it controls what goes in and out of the cell.
The cell membrane
the membrane
cell membrane