A macromolecule is a very large molecule, such as protein, commonly created by the polymerization of smaller subunits (monomers). They are typically composed of thousands of atoms or more. The most common macromolecules in biochemistry are biopolymers (nucleic acids, proteins, carbohydrates and lipids) and large non-polymeric molecules (such as lipids and macrocycles). Synthetic macromolecules include common plastics and synthetic fibers as well as experimental materials such as carbon nanotubes.

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