The cell membrane consists of a phospholipid bilayer with embedded proteins. ... The membrane is selectively permeable because substances do not cross it indiscriminately. Some molecules, such as hydrocarbons and oxygen can cross the membrane.

Why are cell membranes selectively permeable?

The cell membrane is selectively permeable, meaning it only lets certain things in and out of the cell. ... A cell is a living thing and needs just the right balance of nutrients and water, called homeostasis. The selective permeability of the membrane allows the cell to stay in homeostasis.

What is selective permeability of the cell membrane?

Definition. A feature and a function of the plasma membrane that is essential to maintain homeostasis by regulating the passage of some substances while preventing others from entering the cell. Supplement.