The secondary structure of proteins is derived from

Options

A. Hydrogen bonding
B. peptide linkage
C. Folding of chains
D. Disulphide linkage

Answer

To solve the question regarding the secondary structure of proteins, we can follow these steps:

### Step 1: Understand the Structure of Proteins
Proteins have four levels of structure: primary, secondary, tertiary, and quaternary. The secondary structure specifically refers to the local folded structures that form within a protein due to interactions between the backbone atoms.

**Hint:** Recall the four levels of protein structure and focus on the secondary level.

### Step 2: Identify the Key Interactions in Secondary Structure
The secondary structure of proteins is primarily stabilized by hydrogen bonds. These bonds occur between the carbonyl oxygen of one amino acid and the amide hydrogen of another, which is part of the polypeptide backbone.

**Hint:** Think about the types of interactions that stabilize structures in proteins.

### Step 3: Analyze the Options Given
- **Option 1: Hydrogen bonding** - This is the correct answer as it describes the interactions that stabilize the secondary structure.
- **Option 2: Peptide linkage** - This refers to the covalent bonds that link amino acids together in the primary structure, not the secondary structure.
- **Option 3: Folding of chain** - While folding is important, it is not a specific interaction like hydrogen bonding.
- **Option 4: Disulphide linkage** - This is a covalent bond that contributes to the tertiary structure, not the secondary structure.

**Hint:** Evaluate each option based on your understanding of protein structure.

### Step 4: Conclude the Answer
Based on the analysis, the secondary structure of proteins is derived from hydrogen bonding, which is option number 1.

**Final Answer:** The secondary structure of proteins is derived from **hydrogen bonding** (Option 1).