Experimental varification of the chromosomal theory of inheritance done by Thomas Hunt Morgan and his colleagues. They worked with

Options

A. Pea plant
B. Sweet pea plant
C. Snapdragon
D. Drosophila

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Chromosomal Theory of Inheritance**: The chromosomal theory of inheritance states that genes are located on chromosomes, and that the behavior of chromosomes during meiosis explains the inheritance patterns of traits.

2. **Thomas Hunt Morgan's Research**: Thomas Hunt Morgan and his colleagues conducted experiments to verify this theory. They focused on the inheritance patterns of traits in certain organisms.

3. **Choice of Organism**: Morgan chose to work with *Drosophila melanogaster*, commonly known as the fruit fly. This organism was ideal for genetic studies due to its short life cycle, ease of breeding, and the ability to produce a large number of offspring.

4. **Dihybrid Crosses**: Morgan performed various dihybrid crosses (crosses involving two traits) in *Drosophila*. He observed how different traits were inherited together, which led to the discovery of sex-linked inheritance.

5. **Sex-linked Genes**: Morgan specifically studied sex-linked traits, which are traits associated with genes located on the sex chromosomes (X and Y). His experiments demonstrated that certain traits did not segregate independently, supporting the chromosomal theory of inheritance.

6. **Conclusion**: The correct answer to the question about the organism used by Morgan for his experiments is *Drosophila*.

**Final Answer**: Drosophila

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