Question

Match List - I with List - II. 

Choose the correct answer from the options given below : 
 

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

Hint:

Break down complex biological words: "Ecto" = Outside (Extracellular). "Endo" = Inside (Intracellular). Denature = To take away its natural shape (unfolding).

Answer 1

The Correct Option is B

Step 1: Concept:
This question requires matching specific biochemical terminology related to protein architecture, folding, and cellular localization to their correct definitions.

Step 2: Step-by-step Explanation:

• A. Primary structure: This is the most fundamental level of protein architecture. It simply refers to the specific linear Amino acid sequence of a polypeptide chain linked by peptide bonds, dictated directly by DNA. Thus, A matches with II.

• B. Motif: In structural biology, a motif (or supersecondary structure) is a recognizable folding pattern involving a short amino acid sequence with characteristic properties that appears in many different proteins (e.g., a zinc finger or a helix-turn-helix motif). Thus, B matches with III.

• C. Ectodomain: Proteins embedded in the cell membrane have different functional parts. The "ecto" (meaning outside) domain is the Part of a single-pass membrane protein that lies on the exterior (extracellular) side of the cell membrane, often involved in binding ligands. Thus, C matches with IV.

• D. Denaturation: This is the physical or chemical process of Unfolding a protein or a domain, destroying its complex 3D shape (secondary, tertiary, and quaternary structures) without breaking the primary sequence peptide bonds, causing loss of function. Thus, D matches with I.

• Compiling the correct pairs yields: A-II, B-III, C-IV, D-I.

Step 3: Final Answer:
Option (B) represents the correct sequence of matches.