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 usually made of

Options

A. 20 types of monomers
B. 40 types of monomers
C. 30 types of monomers
D. only one type of monomer

Explanation

**Step-by-Step Solution:**

1. **Understanding Homopolymers and Heteropolymers:**
- A homopolymer is a polymer made up of only one type of monomer repeated multiple times.
- A heteropolymer, on the other hand, consists 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 monomers.

3. **Determining the Building Blocks of Proteins:**
- The building blocks of proteins are amino acids. There are 20 different types of amino acids that can be combined in various sequences to form proteins.

4. **Structure of Amino Acids:**
- Each amino acid consists of:
- A central carbon atom.
- An amino group (-NH2).
- A carboxyl group (-COOH).
- A hydrogen atom.
- A variable R-group (side chain) that distinguishes one amino acid from another.

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

**Final Answer:**
Proteins are heteropolymers usually made of 20 different types of monomers called amino acids.

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