Match List-I (type of linkages) with List-II (Biomolecules)

Choose the correct answer from the options given below:

(A)-(II), (B)-(III), (C)-(IV), (D)-(I)

The correct answer is Option (3) → (A)-(II), (B)-(III), (C)-(IV), (D)-(I)

(A) Glycosidic linkage — (II) Disaccharide

A glycosidic linkage is a covalent bond that joins a carbohydrate (sugar) molecule to another group, which may or may not be another carbohydrate. In a disaccharide (like sucrose or lactose), two monosaccharides are joined by this linkage.

(B) Peptide Linkage — (III) Primary structure of proteins

The primary structure of a protein is the linear sequence of amino acids. These amino acids are held together by peptide linkages (amide bonds), formed between the carboxyl group of one amino acid and the amino group of the next.

(C) Phosphodiester linkage — (IV) Nucleotide

In nucleic acids (DNA/RNA), nucleotides are joined together by phosphodiester linkages. This bond connects the 3' carbon atom of one sugar molecule and the 5' carbon atom of another, creating the "backbone" of the strand.

(D) Disulfide linkage — (I) Tertiary structure of proteins

The tertiary structure refers to the overall three-dimensional folding of a polypeptide chain. This structure is stabilized by various interactions, including disulfide linkages (S-S bonds) between the thiol groups of cysteine residues.