Primary proteins are also called as polypeptides because :
- They can assume many conformations
- They are linear chains
- They are polymers of peptide monomers
- Successive amino acids are joined by peptide bonds
Answer
(4) Successive amino acids are joined by peptide bonds
Solution
As per NCERT, proteins are polypeptides; they are linear chains of amino acids linked by peptide bonds.
A peptide bond is formed when the carboxyl (-COOH) group of one amino acid reacts with the amino (-NH2) group of the next amino acid with the elimination of a water molecule.
∵ Successive amino acids are joined by peptide bonds, a protein is called a polypeptide.
Answer: (4)