American bullfrogs inhabit various habitats<span>, such as lakes, ponds, marshes, slow flowing rivers and streams.</span>
        
                    
             
        
        
        
It attracts insects which in turns aid pollination.
        
             
        
        
        
<span>At least 50% of the variation in the trait in the population is due to genetic differences.</span>
        
                    
             
        
        
        
<span>Atherosclerosis is the general term for narrowing and hardening of the arteries due to plaque buildup. When this occurs in the vessels that supply the heart, it is termed coronary artery disease, or coronary heat disease.</span>
        
             
        
        
        
Answer:
<h2>
Codon
</h2>
Explanation:
The sequence of DNA is transcribed into mRNA, containing the sequence  for protein synthesis, protein is synthesized according to the codons in mRNA.  This sequence of nucleotide on DNA/ RNA is divided into a series of three nucleotide units, and one unit of three nucleotide is  known as codons.
There are overall 64 codons, 61 codons out of 64 codons, codes for overall 20  amino acids, and the remaining three  are stop codons.
These there codon do not code for any amino acid.
And these 61 codons, they  code for total 20 amino acids. So one amino acid can be coded by one or more than one codons.