Answer:
Different sequence of amino acid and sequence of DNA.
Step-by-step explanation:
All proteins are made of same amino acids but differ in their function because of different sequence of amino acids. The presence of different sequence is dictated by the nucleotide sequence of their genes. This different sequence of amino acid and sequence of DNA are the factors that are responsible for the different function of different proteins so we can conclude that sequence of amino acid and sequence of DNA are responsible for difference in function of proteins.