The plasma membrane consists mainly of:
Phospholipids embedded in a protein bilayer
Proteins embedded in a phospholipid bilayer
Proteins embedded in a polymer of glucose molecules
Proteins embedded in a carbohydrate bilayer
The membrane that separates the cell's interior from its external environment is called the plasma membrane.
It primarily consists of a phospholipid bilayer embedded with globular proteins, carbohydrates, and conjugated molecules.
The phospholipids have a hydrophilic exterior and a hydrophobic interior. The semipermeable plasma membrane controls the flow of substances into and out of the cell.
Hence, the correct answer is option 2).