Which cellular structure controls what enters and exits the cell?
-
Mitochondrion
-
Cell wall
-
Nucleus
-
Cell membrane
D
Correct answer
Explanation
The cell membrane (or plasma membrane) is selectively permeable, meaning it regulates the passage of substances into and out of the cell. The cell wall provides structural support but is fully permeable, while the nucleus and mitochondria have different metabolic and genetic functions.