Coupling and repulsion theory was introduced by

Options

A. Morgan
B. Bateson
C. Muller
D. De vries

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the origin of the coupling and repulsion theory in genetics.

2. **Defining Key Terms**:
- **Linkage**: This refers to the physical association of two genes on the same chromosome. Genes that are close together are more likely to be inherited together.
- **Coupling and Repulsion**: These are two aspects of how alleles can be arranged on chromosomes.

3. **Explaining Linkage**:
- When two genes are located close to each other on a chromosome, they tend to be inherited together. This is known as linkage.
- The closer the genes are, the less likely they are to undergo recombination during meiosis.

4. **Introducing Coupling and Repulsion Theory**:
- The coupling and repulsion theory explains how alleles can be arranged on homologous chromosomes.
- In the coupling aspect, both dominant alleles of two genes are located on the same chromosome.
- In the repulsion aspect, one dominant allele and one recessive allele are on the same chromosome.

5. **Identifying the Contributor**:
- The theory of coupling and repulsion was introduced by **Bateson**.

6. **Conclusion**: Therefore, the answer to the question is that coupling and repulsion theory was introduced by **B. Bateson**.

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