Who proved that genes are located on chromosomes?

Options

A. Sutton and Boveri (1902)
B. Johanssen (1909)
C. Morgan (1910)
D. Muller (1927)

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks who proved that genes are located on chromosomes. This involves identifying the scientist or scientists who made significant contributions to this discovery.

2. **Analyzing the Options**: The options provided are Sutton and Boveri, Johanson, Morgan, and Muller. We need to evaluate each option based on their contributions to genetics.

3. **Evaluating Sutton and Boveri**: Sutton and Boveri are known for their work related to the chromosomal theory of inheritance. They established that there is a parallel relationship between chromosomes and genes, but they did not directly prove that genes are located on chromosomes.

4. **Evaluating Johanson**: Johanson is known for his contributions to the concepts of phenotype and genotype. His work does not specifically address the location of genes on chromosomes.

5. **Evaluating Muller**: Muller is recognized for his work on mutations, particularly how x-rays can induce mutations. While important, this does not pertain to the location of genes on chromosomes.

6. **Identifying the Correct Answer**: The correct answer is Morgan. Thomas Hunt Morgan conducted experiments with Drosophila (fruit flies) and concluded that genes are located on chromosomes. His work provided substantial evidence for the chromosomal theory of inheritance.

7. **Conclusion**: Therefore, the scientist who proved that genes are located on chromosomes is Thomas Hunt Morgan.

**Final Answer**: Thomas Hunt Morgan.

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