Q.Classify the following as natural or synthetic polymers, giving a reason for each:

Starch is a polymer of glucose units produced and stored by plants as a food reserve, and is therefore a natural polymer -- no laboratory synthesis is involved in its formation in nature. Natural rubber is a polymer of isoprene units biosynthesised by the rubber tree, Hevea brasiliensis, and tapped as latex, so it too is a natural polymer. Nylon-6,6, in contrast, does not occur anywhere in nature: it is manufactured entirely in the factory by condensing two synthetic organic monomers, hexamethylenediamine and adipic acid, so it is a synthetic polymer. Polythene likewise has no natural source -- it is manufactured by polymerising the small monomer ethene under controlled industrial conditions, so it too is synthetic.

Ask whether the polymer is produced ready-made by a living organism (natural) or is manufactured from small organic monomers in the laboratory/factory (synthetic).

Assuming any 'plastic-like' or fibre material must be synthetic; forgetting that rubber, despite behaving like many synthetic elastomers, is itself of natural (plant) origin unless specified as a synthetic rubber like Buna-S or Buna-N.