A mutation in DNA molecule involing replacement of one nucleiotide base pair with another is

Answer

### Step-by-Step Solution:

1. **Understanding the Mutation**: The question describes a mutation involving the replacement of one nucleotide base pair with another. This indicates a change at a specific point in the DNA sequence.

2. **Identifying Types of Mutations**: There are different types of mutations in DNA, including point mutations and frameshift mutations. A point mutation involves a change in a single nucleotide, while a frameshift mutation involves the insertion or deletion of nucleotides that shifts the reading frame.

3. **Example of Point Mutation**: An example of a point mutation is seen in sickle cell anemia, where a single nucleotide change occurs. Specifically, the codon for glutamic acid (GAG) is replaced by the codon for valine (GUG) due to a mutation.

4. **Conclusion**: Since the question specifically mentions the replacement of one nucleotide base pair with another, this type of mutation is classified as a **point mutation**.

### Final Answer:
A mutation in a DNA molecule involving the replacement of one nucleotide base pair with another is called a **point mutation**.

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