A homopolymer has only one type of building block called monomer repeated ‘n’ number of times. A heteropolymer has more than one type of monomer. Proteins are heteropolymers usually made of

1.  20 types of monomers

2.  40 types of monomers

3.  30 types of monomers

4.  only one type of monomer

Proteins perform many physiological functions. For example, some functions as enzymes. One of the following represents an additional function that some proteins discharge

1.  Antibiotics

2.  Pigment conferring colour to skin

3.  Pigments making coloursof flowers

4.  Hormones