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.
Main article: Cell membrane. The cell membrane, or plasma membrane, is a biological membrane that surrounds the cytoplasm of a cell. In animals, the plasma membrane is the outer boundary of the cell, while in plants and prokaryotes it is usually covered by a cell wall.