How many polypeptide chains are in a protein?

Answer 1

There is one polypeptide chain in a single protein chain.

Polypeptides refer to short protein chains - for example insulin is a 53 amino acid protein and is considered a large polypeptide.

Complex multi-component [strand] protein coalescences exist - each uniquely identified component protein strand is called - of course - a subunit: two subunits is called a dimer, three subunits is called a trimer, four is a tetramer etc.

A Protein is a string of Pearls {Amino Acids} of which [out of the quadrillion possible] there are ONLY Twenty Biologically Active Types ( with two, sometimes three, more reserved for special occasions ).

A common example of a biological multi-strand protein grouping is: 4 strands will combine thusly - 2 strands of one type and 2 strands of another type.

Answer 2

Four polypeptide chains (2 heavy chains and 2 light chains) are present in an antibody molecule in its monomeric form.

Answer 3

None. The genetic code is in the nucleic acids, not the polypeptides.

Answer 4

Two or more polypeptide chains exist in the quaternary structure.

It could be two (a dimer), three (a trimer), four (a tetramer), or more.