Point out the incorrect statemet regarding proteins.

Options

A. Most of enzymes and may hormones are proteins
B. Proteins are stuctural components of membrane.
C. Proteins are high energy yieldin compounds.
D. Immunglobulins are proteins.

Answer

To identify the incorrect statement regarding proteins, we will analyze each statement provided in the question.

### Step-by-Step Solution:

1. **Understanding Proteins**:
- Proteins are essential biological macromolecules made up of 20 standard amino acids.
- These amino acids are linked together by peptide bonds to form long polypeptide chains, which fold into functional proteins.

2. **Evaluating the Statements**:
- **Statement 1**: "Most of enzymes and many hormones are proteins."
- This statement is **correct**. Enzymes and hormones are indeed proteins that play crucial roles in biological processes.

- **Statement 2**: "Proteins are structural components of membranes."
- This statement is also **correct**. Proteins are integral components of cell membranes, including integral and peripheral proteins that contribute to the structure and function of the membrane.

- **Statement 3**: "Proteins are high energy yielding compounds."
- This statement is **incorrect**. While proteins can provide energy, they are not considered high energy yielding compounds compared to carbohydrates and fats. The primary energy carriers in the body are ATP, NADPH, and FAD.

- **Statement 4**: "Immunoglobulins are proteins."
- This statement is **correct**. Immunoglobulins, or antibodies, are indeed proteins that play a vital role in the immune response.

3. **Conclusion**:
- The incorrect statement regarding proteins is: **"Proteins are high energy yielding compounds."** This is the answer to the question.