Answer:
Due to number of amino acids.
Explanation:
The main differences might be expected in the amino acid composition of X versus Y because the X polypeptide is made up of one smaller unit of amino acid while on the other hand, Y polypeptide is made up of four smaller units of amino acids. The name of X is monomer which means composed of one amino acids while Y exists as a tetramer which means it has four amino acids. So we can conclude that the main difference between X and Y is the presence of number of amino acids.
Elements cannot be broken down to similar substances.
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