Hi, Jalissa7!
The plasma membrane in a cell is the surrounding layer of the cell that protects it and regulates what is allowed to enter and exit a cell at any given time. The plasma membrane is made up of a phospholipid bilayer.
A phospholipid bilayer has a hydrophilic, or water-loving, exterior, and a hydrophobic, or water-hating, interior. This layer is made up of fatty acids and proteins.
-ASIAX Frequent Answerer
