The total number of amino acids which occur in proteins

Options

A. 10
B. 20
C. 200
D. 24

Answer

To solve the question regarding the total number of amino acids that occur in proteins, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Proteins**:
- Proteins are macromolecules that play essential roles in living organisms. They serve as building blocks for cells and tissues.

2. **Monomeric Units of Proteins**:
- Proteins are polymers made up of smaller units called amino acids. These amino acids are the monomers that combine in various sequences to form different proteins.

3. **Total Number of Amino Acids**:
- While there are over 300 amino acids that exist in nature, only 20 of these amino acids are commonly used in the synthesis of proteins in living organisms.

4. **Identifying the Correct Answer**:
- The question specifically asks for the total number of amino acids that occur in proteins. Since only 20 amino acids are utilized to encode for proteins, the answer to the question is 20.

5. **Conclusion**:
- Therefore, the total number of amino acids which occur in proteins is **20**.

### Final Answer:
The total number of amino acids which occur in proteins is **20**.

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