Answer:
It would make it possible to compare that species to other species at a level deeper than outward appearance
Explanation:
The proteins like hemoglobin and enzymes can be studied to see whether organism which are similar in form can also be related to each other. Its differences found in these proteins' amino acid sequences will present how closely or distantly related an organism is to another.
I'm new here and this is one of the first things i've done on this site but to answer the question, i believe the answer is amino acids
Gallons. You buy gasoline by the gallon.