Answer: 1. separates the material inside the cell from the outside environment
2. also allows material to pass in and out of the cell, if it is safe to do so
3. protects the nucleus and cytoplasm
Explanation: Mitochondria is the powerhouse of the cell. So thats not right. The other three are right. The cell membrane protects the cell by either blocking material that tries to come to the cell or pushing out material from within the shell.
The plasma membrane, or the cell membrane, provides protection for a cell. It also provides a fixed environment inside the cell, and that membrane has several different functions. One is to transport nutrients into the cell and also to transport toxic substances out of the cell.
