E emucompboy New member Oct 22, 2009 #2 The cell membrane is selectively permeable. It allows the cell to keep out stuff that the cell does not need, and keep in what the cell does need. It's not like a bacterium that lives in sand is going to be made of silicon dioxide, right?
The cell membrane is selectively permeable. It allows the cell to keep out stuff that the cell does not need, and keep in what the cell does need. It's not like a bacterium that lives in sand is going to be made of silicon dioxide, right?
