Which of the following is not a property of the genetic code ?

Options

A. Non-overlapping
B. Degeneracy
C. Universal
D. Ambiguous

Answer

To determine which of the following is not a property of the genetic code, we will analyze each option provided:

1. **Non-overlapping**:
- The genetic code is non-overlapping, meaning that each nucleotide in the mRNA is part of only one codon. For example, if we have a sequence of nucleotides, they are read in groups of three (codons) without sharing nucleotides between them. Thus, this property is true for the genetic code.

2. **Degeneracy**:
- The genetic code is degenerate, which means that multiple codons can code for the same amino acid. For instance, there are several codons that can code for the amino acid leucine. Therefore, this property is also true for the genetic code.

3. **Universal**:
- The genetic code is considered universal because the same codons generally code for the same amino acids across different organisms. For example, the codon AUG codes for methionine in both humans and bacteria. Hence, this property is true as well.

4. **Ambiguous**:
- The genetic code is non-ambiguous, meaning that each codon specifies only one amino acid. For example, the codon UUU will always code for phenylalanine and not for any other amino acid. Therefore, the property of being ambiguous is incorrect in the context of the genetic code.

Based on the analysis, the option that is **not** a property of the genetic code is **d. ambiguous**.

### Summary of Steps:
1. Identify the properties of the genetic code.
2. Analyze each option provided in the question.
3. Determine which option does not align with the established properties of the genetic code.
4. Conclude that the correct answer is **d. ambiguous**.