The conversion of mutant type into wild type is called

Options

A. backward mutation
B. forward mutation
C. inversion
D. both (2) and (3) correct

Answer

To solve the question "The conversion of mutant type into wild type is called," we will analyze the options provided and understand the concepts of mutations.

### Step-by-Step Solution:

1. **Understand the Definitions:**
- **Mutation:** A mutation is a sudden change in the genetic material of an organism. This can be caused by environmental factors or chemical agents.
- **Wild Type:** This refers to the typical form of a species, which is usually the most common phenotype or genotype found in nature.
- **Mutant Type:** This is a variant form that differs from the wild type, often due to a mutation.

2. **Analyze the Options:**
- **Option 1: Backward Mutation**
- A backward mutation refers to the process where a mutant type reverts back to the wild type. This means that a non-functional gene (mutant) becomes functional again (wild type).
- **Option 2: Forward Mutation**
- A forward mutation is the opposite; it refers to the change from wild type to mutant type. This is not relevant to our question.
- **Option 3: Inversion**
- Inversion is a specific type of mutation where a segment of DNA is reversed within the chromosome. This does not pertain to the conversion of mutant to wild type.
- **Option 4: Both 2nd and 3rd**
- This option combines the incorrect options of forward mutation and inversion, making it incorrect as well.

3. **Conclusion:**
- Based on the definitions and analysis, the correct answer to the question is **Option 1: Backward Mutation**. This is the term used to describe the conversion of mutant type back into wild type.

### Final Answer:
The conversion of mutant type into wild type is called **Backward Mutation**.

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