Select the incorrect statement .

Options

A. 'Hb' is an example of quaternary structure of protein
B. In the primary structure of protein , the left hand is C - terminal and the right hand is N-terminal.
C. In protein or polypeptide , the amino acids are linked by peptide bond.
D. Most of the enzyme are Protein in nature.

Answer

To solve the question of selecting the incorrect statement, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement 1: Hemoglobin is an example of quaternary structure of protein.**
- Hemoglobin (Hb) is indeed a protein that exhibits a quaternary structure. It consists of four subunits: two alpha and two beta chains. This statement is **correct**.

2. **Statement 2: The left end is C-terminal and the right end is N-terminal in the primary structure of protein.**
- In the primary structure of proteins, the left end is the N-terminal (where the first amino acid is located) and the right end is the C-terminal (where the last amino acid is located). This statement incorrectly describes the ends of the protein. Therefore, this statement is **incorrect**.

3. **Statement 3: Amino acids are linked by peptide bonds in proteins and polypeptides.**
- This statement is correct. Amino acids are indeed linked together by peptide bonds to form proteins and polypeptides.

4. **Statement 4: Most of the enzymes are protein in nature.**
- This statement is also correct. Most enzymes are proteins that catalyze biochemical reactions.

### Conclusion:
The incorrect statement is **Statement 2**: "The left end is C-terminal and the right end is N-terminal in the primary structure of protein."

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