`overset((A))("_____")` used the frequency of recombination between gene pairs on the `overset((B))("_____")` as a measure of the distance between genes and mapped their position on the chromosome.

Options

A. `{:("A","B"),("Morgan","Same chromosome"):}`
B. `{:("A","B"),("Sturtevant","Different chromosomes"):}`
C. `{:("A","B"),("Morgan","Different chromosomes"):}`
D. `{:("A","B"),("Sturtevant","Same chromosome"):}`

Answer

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

1. **Identify the Scientist**: The first part of the question asks for the name of the scientist who used the frequency of recombination between gene pairs. The correct answer is "Morgan". Morgan is known for his work in genetics and for establishing the concept of genetic linkage and mapping.

2. **Understand the Concept of Recombination**: The second part of the question refers to the location where the frequency of recombination is measured. This is done on the "same chromosome". Genes that are located on the same chromosome can be linked, and their recombination frequency can be used to determine their relative positions.

3. **Fill in the Blanks**: Based on the information gathered:
- For fill-in (A), the answer is "Morgan".
- For fill-in (B), the answer is "same chromosome".

4. **Final Answer**: Therefore, the complete statement reads: "Morgan used the frequency of recombination between gene pairs on the same chromosome as a measure of the distance between genes and mapped their position on the chromosome."

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