Answer:
Plasma membrane is made up of a phospholipid bilayer. To be more exact there is two fatty acids making up the polar hydrophilic head, and a phosphate group attached as the non-polar hydrophobic tail. Proteins have many uses in regards to the cell membrane. In a nutshell they are used for diffusion of molecules across the plasma membrane. They are different types of diffusion, most noteably you should try and know the different between passive and active transport the latter of which involves a protien pump. Carbohydrates are used for cushiing the cell membrane and for cell recognition.
Explanation: I learned this in class, I'm in IB Bio HL