Question

Match List-I with List-II:

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

Answer 1

The Correct Option is A

To match List-I with List-II correctly, we need to understand the characteristics and associations of fibrous proteins and their functions.

List-I	List-II
A. Keratin	I. Structural protein found in hair and nails
B. Collagen	II. Fibrous protein in connective tissues
C. Fibroin	IV. Protein found in silk
D. Elastin	III. Provides elasticity to tissues

Based on the properties and locations of these proteins, we can establish the following associations:

• Keratin is a structural protein important for hair and nails, aligning with I.
• Collagen is a fibrous protein primarily found in connective tissues, matching with II.
• Fibroin is known as the protein found in silk, so it matches with IV.
• Elastin provides elasticity and is significant for tissues, aligning with III.

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

Answer 2

(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.