<unk> s are carbohydrate-attached lipids.  Their role is to provide energy and also serve as markers for cellular recognition.
They occur where a carbohydrate chain is associated with phospholipids on the exoplasmic surface of the cell membrane. The carbohydrates are found on the outer surface of all eukaryotic cell membranes.
They extend from the phospholipid bilayer into the aqueous environment outside the cell where it acts as a recognition site for specific chemicals as well as helping to maintain the stability of the membrane and attaching cells to one another to form tissues.
Glycolipid
Phospholipid
Diatomic molecule
Nucleic acid
Nucleoside
Glycerophospholipid
Glycoprotein
Polyphosphate