A phospholipid bilayer consists of two layers of phospholipids.
Phospholipid consists of hydrophilic phosphate head and hydrophobic hydrocarbon tail.
Phospholipids are fluid so they can change shape and vesicles can be pinched off or fuse with membranes.
Membrane proteins have a number of uses:
- hormone binding,
- electron carrier,
- passive transport,
- active transport