Adaptations-. Black bears have a thick layer of fur for the cold winters,claws to climb trees and stay away from danger along with sharp teeth for protection like scaring away predators and to tear apart fish.Bears also hibernate in the winter to avoid having to find food which is difficult in the winter.
The cell membrane, or plasma membrane, surrounds and protects the internal environment of a cell; however, this is not its only function. A cell membrane also determines what materials enter or leave the cell. This ensures that the cells will be able to get rid of wastes and take up important nutrients and gases.
the plasma membrane is the boundary between the cell and its environment it regulates what enters and exits the cell cells must maintain an appropriate amount of molecules to function inside them they must also have a way to keep things out or to allow things to enter this is the job of the plasma membrane