A homopolymer has only one type of building block called monomer repeated 'n' number of times. A heteropolymer has more than one type of monomer. Proteins are heteropolymers made of amino acids. While a nucleic acid like DNA or RNA is made of only 4 types of nucleotide monomers, proteins are made of

Options

A. 20 types of monomers
B. 40 types of monomers
C. 3 types of monomers
D. Only one type of monomer

Answer

**Step-by-Step Text Solution:**

1. **Understanding Homopolymers and Heteropolymers:**
- A homopolymer consists of only one type of monomer repeated multiple times. For example, glycogen is a homopolymer made entirely of glucose units.
- In contrast, a heteropolymer is composed of more than one type of monomer.

2. **Identifying Proteins as Heteropolymers:**
- Proteins are classified as heteropolymers because they are made up of different types of building blocks known as amino acids.

3. **Types of Monomers in Proteins:**
- There are 20 different amino acids that serve as the monomeric units for proteins. Each amino acid has a unique structure and properties due to its specific side chain (R group).

4. **Classification of Amino Acids:**
- Amino acids can be categorized based on their properties:
- **Polar and Non-Polar Amino Acids:** Depending on the nature of their side chains.
- **Acidic and Basic Amino Acids:** Based on the presence of acidic or basic functional groups.
- **Essential and Non-Essential Amino Acids:** Essential amino acids cannot be synthesized by the body and must be obtained from the diet, while non-essential amino acids can be synthesized by the body.

5. **Conclusion:**
- Therefore, proteins are heteropolymers made up of 20 different types of amino acids.

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