Proteins are condensation polymers of

Options

A. `alpha`-Amino acids
B. `beta`-Amino acids
C. `alpha`-Hydroxy acids
D. `beta`-Hydroxy acids

Answer

### Step-by-Step Solution:

1. **Understanding Proteins**: Proteins are large biomolecules essential for various biological functions. They are made up of smaller units called amino acids.

2. **Definition of Condensation Polymer**: A condensation polymer is formed when monomers join together with the elimination of a small molecule, often water. In the case of proteins, the monomers are amino acids.

3. **Identifying Amino Acids**: Amino acids are organic compounds that contain both an amine group (-NH2) and a carboxylic acid group (-COOH). They can be classified into different types based on the position of these functional groups.

4. **Alpha-Amino Acids**: The most common type of amino acids that form proteins are alpha-amino acids. In these amino acids, the amine group is attached to the carbon atom adjacent to the carboxylic acid group, known as the alpha carbon.

5. **Formation of Peptide Bonds**: When two amino acids undergo a condensation reaction, they form a peptide bond (CO-NH bond) and release a water molecule. This process can continue to form longer chains of amino acids, known as polypeptides or proteins.

6. **Conclusion**: Therefore, proteins are condensation polymers of alpha-amino acids.

### Final Answer:
Proteins are condensation polymers of **alpha-amino acids**.

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