What component of amino acid structure varies among different amino acids?

a. the glycerol molecule that forms the backbone of the amino acid

b. the location of the carboxyl group

c. the long carbon-hydrogen tails of the molecule

d. the components of the r group?

Answer

The components of the r group of amino acid structure varies among different amino acids

Explanation

As the functional group for amino acids is as:

R-CH-COOH

I

NH2

only R differs so amino acids also differs. If R is "H" then amino acid is glycine and if R is "CH3" then amino acid is alanine. Hence, R is different for different amino acids. Other components as alpha carbon (C), carboxyl group (COOH) and amino group (NH2) is fixed for every amino acid.