Match List I with List II

Choose the correct answer from the options given below:

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

The correct answer is option 1. A-I, B-II, C-IV, D-III

(A) Amino acids linked in a specific sequence: (I) Primary structure of proteins:

The primary structure of a protein refers to the linear sequence of amino acids that are linked together by peptide bonds. This sequence determines the unique identity of each protein.

(B) Regular folding of a specific sequence of amino acids due to H-bonding: (II) Secondary structure of proteins:

Secondary structure refers to the regular folding patterns adopted by localized regions of the polypeptide chain. These folding patterns are stabilized by hydrogen bonds between the backbone atoms of amino acids. Common secondary structures include alpha helices and beta sheets.

(C) Fibrous proteins: (IV) Tertiary structure of proteins

Fibrous proteins are characterized by long, elongated shapes with a repeating pattern. The tertiary structure refers to the three-dimensional arrangement of the entire polypeptide chain, including the folding and bending of the secondary structures. Fibrous proteins like collagen and keratin exhibit a distinct tertiary structure.

(D) Spatial arrangement of two or more polypeptide chains (III) Quaternary structure of proteins:

Quaternary structure refers to the spatial arrangement of multiple polypeptide chains (subunits) within a protein complex. Proteins with quaternary structure are composed of two or more individual polypeptide chains, which may interact to form a functional protein assembly.

The primary structure describes the linear sequence of amino acids.

Secondary structure involves regular folding patterns stabilized by hydrogen bonds.

Tertiary structure encompasses the overall three-dimensional arrangement of a single polypeptide chain.

Quaternary structure involves the spatial arrangement of multiple polypeptide chains in a protein complex.

Therefore, the correct matching is: 3. A-I, B-II, C-IV, D-III