Assume that there are 6 types of nitrogen bases available and 40 types of amino acid are available for protein synthesis, then in genetic code each codon made up by minimum how many nitrogen bases ?

Options

A. 3
B. 4
C. 5
D. 2

Answer

To solve the problem of determining the minimum number of nitrogen bases required to form a codon when there are 6 types of nitrogen bases and 40 types of amino acids, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Codons**: A codon is a sequence of nitrogen bases that corresponds to a specific amino acid. Each amino acid is coded by a specific sequence of nitrogen bases.

2. **Identify the Available Nitrogen Bases and Amino Acids**: In this case, we have 6 types of nitrogen bases and 40 types of amino acids.

3. **Calculate the Number of Codons Possible with Different Lengths**:
- For a codon made up of **2 nitrogen bases**: The total combinations would be \(6^2 = 36\) codons.
- For a codon made up of **3 nitrogen bases**: The total combinations would be \(6^3 = 216\) codons.

4. **Compare the Number of Codons to the Number of Amino Acids**:
- With **2 nitrogen bases**, we can only form 36 codons, which is less than the 40 amino acids needed. Therefore, 2 bases are insufficient.
- With **3 nitrogen bases**, we can form 216 codons, which is more than enough to code for the 40 amino acids. Thus, 3 bases are sufficient.

5. **Conclusion**: Since 3 nitrogen bases can produce enough codons to code for all 40 amino acids, the minimum number of nitrogen bases required for one codon is **3**.

### Final Answer:
The minimum number of nitrogen bases in each codon is **3**.

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