The cell membrane is composed of phospholipids, proteins involved in transport, cholesterol, and aquaporins. What is this membrane commonly called?

• A. Phospholipid Membrane
• B. Nuclear Membrane
• C. Ribosomal Membrane
• D. Mitochondrial Membrane

Answer: (A)

The cell boundary is built as a phospholipid bilayer with embedded proteins, cholesterol, and channels like aquaporins, giving it a flexible, selective barrier for transport. Because this membrane is defined by its phospholipid composition, it’s commonly referred to as the phospholipid membrane. In everyday terms it’s also called the plasma membrane or cell membrane, but the emphasis on the lipid bilayer makes this naming most descriptive for the given description. Other membranes exist for organelles—such as the nuclear membrane surrounding the nucleus or mitochondrial membranes around mitochondria—so they don’t match the general cell boundary described here.