End groups are an important aspect of polymer synthesis and characterization.
The International Union of Pure and Applied Chemistry (IUPAC) is an international federation of National Adhering Organizations that represents chemists in individual countries.
A macromolecule is a very large molecule, such as protein, commonly created by the polymerization of smaller subunits (monomers).
A monomer (mono-, "one" + -mer, "part") is a molecule that "can undergo polymerization thereby contributing constitutional units to the essential structure of a macromolecule".
Pure and Applied Chemistry (abbreviated Pure Appl. Chem.) is the official journal for the International Union of Pure and Applied Chemistry (IUPAC).
A repeat unit or repeating unit is a part of a polymer whose repetition would produce the complete polymer chain (except for the end-groups) by linking the repeat units together successively along the chain, like the beads of a necklace.