The kidney is referred to as an excretory organ because it excretes __1__ wastes. it is also a major homeostatic organ because it maintains the electrolyte, __2__ and __3__ balance of the blood.

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