Addition or deletion of a nitrogenous base causes

Options

A. Frameshift mutation
B. Inversion
C. Transformation
D. Trnslocation

Answer

**Step-by-Step Solution:**

1. **Understanding Nitrogenous Bases**: Nitrogenous bases are the building blocks of DNA and RNA. They include adenine (A), thymine (T), cytosine (C), guanine (G), and uracil (U) in RNA.

2. **Identifying Addition or Deletion**: When we talk about the addition or deletion of a nitrogenous base, we are referring to a change in the DNA or RNA sequence. For example, if we have a sequence like A-T-C-G-G-A and we delete one base, say T, the new sequence becomes A-C-G-G-A.

3. **Impact on Codons**: Codons are sequences of three nitrogenous bases that code for specific amino acids. In the original sequence, the codons would be A-T-C, G-G-A. After deletion, the new sequence A-C-G-G-A changes the codons to A-C-G and G-A, which may code for different amino acids.

4. **Understanding Frameshift Mutation**: The addition or deletion of a base shifts the reading frame of the sequence. This means that all subsequent codons are altered, leading to the production of entirely different proteins. This type of mutation is known as a frameshift mutation.

5. **Conclusion**: Therefore, the addition or deletion of a nitrogenous base causes a frameshift mutation, which can lead to significant changes in the resulting protein, potentially altering its function.

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