If modern organisms have a lot of homologous structures, what inference might paleontologists make about those organisms?

They are reptiles

The organisms have a common ancestor.

One organism evolved from the other

Protein and polypeptide sequences can be determined by first partially hydrolyzing the protein or polypeptide followed by amino acid sequencing of the fragment pieces using the chemical degradation process known as edman degradation. determine the sequence of the initial (18-amino acid) polypeptide that produces the following five partial sequences after hydrolysis and edman degradation.