LIFE SCIENCE

Detailed explanation-1: -The R group determines the characteristics (size, polarity, and pH) for each type of amino acid. Peptide bonds form between the carboxyl group of one amino acid and the amino group of another through dehydration synthesis. A chain of amino acids is a polypeptide.

Detailed explanation-2: -Each of the 20 amino acids has a specific side chain, known as an R group, that is also attached to the carbon. The R groups have a variety of shapes, sizes, charges, and reactivities. This allows amino acids to be grouped according to the chemical properties of their side chains.

Detailed explanation-3: -The carbon, carboxyl, and amino groups are common to all amino acids, so the R-group is the only unique feature in each amino acid. (A minor exception to this structure is that of proline, in which the end of the R-group is attached to the -amine.)

Detailed explanation-4: -The amino acid R group is a term that refers to the variable group on each amino acid. The amino acid backbone is identical on all amino acids, the R groups are different on all amino acids.