Final answer:
Cell membranes help maintain homeostasis in cells by regulating the passage of materials.
Step-by-step explanation:
Cell membranes help maintain homeostasis in cells by regulating the passage of materials. The cell membrane is selectively permeable, allowing some substances to pass through while preventing others from entering or leaving the cell. This selective permeability ensures that the cell can maintain a stable internal environment, which is essential for homeostasis. For example, the cell membrane controls the movement of ions, nutrients, and waste products in and out of the cell.