Two or more kinds of alkenes (a type of monomer) can combine to form a polymers. Alkenes are a smaller kind of molecule that are joined through covalent bonds to form polymers (a larger molecule) and produce a different kind of substance.
To create polyester two different kinds of monomers called ETHENE and PROPENE are needed to make double bonds in the chemical reaction.
They both contain membrane-bound organelles such as the nucleus, cell membrane, endomembranes, mitochondria, ribosome, and peroxisome