The smallest of the vertebrate classes, the are represented by only 4,000 species.
a. bony fish
b. jawless fish
c. amphibians
d. sharks

wha is what i will use to get my free points

nucleic acid molecules are incredibly complex, containing the code that guarantees the four different nucleotide units comprise dna, the nucleic acid of interest to the genealogist. and one of four nitrogen-containing molecules called nucleotides