the cell membrane
The cell membrane regulates the flow of materials into and out of the cell. It is selectively permeable, meaning it controls what substances can pass through it. Additionally, membrane proteins and transport channels help facilitate the movement of specific molecules in and out of the cell.
semipermeable cell membrane
cell membrane
The Plasma Membrane
the cell membrane
Cell Membrane
The Cell Membrane Makes Sure that the materials going in and out of the cell are not harmful, such as a virus.
The cell membrane.
Cell Membrane
cell membrane
If I remember correctly, it should be the cell membrane.
The phospholipid bilayer. The cell membrane.