Some amino acids are coded by more than one codon, hence the genetic code is

Options

A. overlapping
B. degenerate
C. wobbled
D. unambiguous

Answer

To answer the question regarding why some amino acids are coded by more than one codon, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Codons**:
- Codons are sequences of three nucleotides in mRNA that specify an amino acid. There are a total of 64 possible codons (4^3 combinations of the four nucleotides: A, U, C, G).

2. **Identifying the Number of Amino Acids**:
- There are 20 standard amino acids that are encoded by these codons.

3. **Recognizing Nonsense Codons**:
- Out of the 64 codons, 3 are nonsense codons (stop codons) that do not code for any amino acid. This leaves us with 61 codons that actually code for amino acids.

4. **Understanding Degeneracy**:
- The genetic code is described as degenerate because multiple codons can code for the same amino acid. This is due to the variability in the third position of the codon, while the first two positions are usually more conserved.

5. **Example of Degeneracy**:
- For instance, the amino acid leucine can be coded by six different codons: UUA, UUG, CUU, CUC, CUA, and CUG. This illustrates how the genetic code allows for redundancy.

6. **Conclusion**:
- Therefore, the genetic code is described as degenerate because it allows for multiple codons to specify the same amino acid.

### Final Answer:
The genetic code is degenerate.