A sudden spontaneous change in structure and action of a gene is called

Options

A. Variation
B. Allelomeorph
C. Linkage
D. Mutation

Answer

To solve the question "A sudden spontaneous change in structure and action of a gene is called," we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for a term that describes a sudden and spontaneous change in the structure and function of a gene.

2. **Analyzing the Options**:
- **Option 1: Variation**: This term refers to changes in organisms that occur over time, often in response to environmental factors. These changes are gradual, not sudden, so this option is incorrect.
- **Option 2: Allelomorph**: This is another term for allele, which refers to different forms of a gene. It does not describe a change but rather a type of gene, so this option is also incorrect.
- **Option 3: Linkage**: Linkage refers to the physical proximity of genes on a chromosome and how they are inherited together. This term does not relate to changes in gene structure or function, making this option incorrect as well.
- **Option 4: Mutation**: This term specifically refers to a sudden change in the structure or function of a gene, which can occur due to various factors such as environmental influences (e.g., radiation). This aligns perfectly with the question.

3. **Conclusion**: After analyzing all the options, the correct answer is **Option 4: Mutation**.

### Final Answer:
A sudden spontaneous change in structure and action of a gene is called **mutation**.

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