Question 34

Peptide bonds are present between the monomers of an enzyme macromolecule.

Enzymes are proteins that are composed of amino acids linked together by peptide bonds. These bonds form between the carboxyl group of one amino acid and the amino group of another, creating a polypeptide chain that constitutes the enzyme.

A) Phosphodiester bonds

Phosphodiester bonds are primarily found in nucleic acids, linking nucleotides together in DNA and RNA. They do not occur between the monomers of proteins, making this option incorrect.

B) Glycosidic bonds

Glycosidic bonds are found in carbohydrates, linking monosaccharides to form disaccharides and polysaccharides. Since enzymes are proteins, this type of bond does not apply to the monomers of enzyme macromolecules, rendering this option incorrect.

C) Ester bonds

Ester bonds are formed between an alcohol and an acid, commonly seen in lipids. They are not involved in the formation of protein structures, such as enzymes, thereby making this option incorrect as well.

D) Peptide bonds

Peptide bonds are the specific type of covalent bond that links amino acids together in proteins. Since enzymes are made up of amino acids, this option correctly identifies the bonds present between the monomers of enzyme macromolecules.

Conclusion

Peptide bonds are the only type of covalent bond that link the amino acid monomers in enzyme macromolecules, making option D definitively correct. All other options refer to bonds that are irrelevant to the structure of proteins, thus confirming that they are incorrect in this context.