The genes for the eye colour and size of the wing in Drosophila are located on the same chromosome. They can be separated by

Options

A. Non -disjunction
B. crossing over
C. Hybridization
D. Not be separated at any stage

Answer

To solve the question regarding the separation of genes for eye color and wing size in Drosophila that are located on the same chromosome, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Gene Location**:
- The genes for eye color and wing size are located on the same chromosome. This means they are linked and tend to be inherited together.

2. **Exploring Gene Separation Mechanisms**:
- We need to identify mechanisms that can separate these linked genes. The options provided are:
- A) Non-disjunction
- B) Crossing over
- C) Hybridization
- D) Not be separated at any stage

3. **Analyzing Non-disjunction**:
- Non-disjunction is the failure of homologous chromosomes to separate during meiosis. This results in gametes with an abnormal number of chromosomes. However, this does not specifically separate linked genes on the same chromosome.

4. **Analyzing Crossing Over**:
- Crossing over occurs during prophase I of meiosis, where homologous chromosomes exchange segments of genetic material. This process can separate linked genes and create new combinations of alleles, leading to recombinant offspring.

5. **Analyzing Hybridization**:
- Hybridization refers to the mating of individuals from different genetic backgrounds to produce hybrids. This does not directly separate genes on the same chromosome.

6. **Conclusion**:
- Since crossing over is the only mechanism that can separate genes located on the same chromosome by exchanging genetic material, the correct answer is:
- **Option B: Crossing over**.

### Final Answer:
The genes for eye color and size of the wing in Drosophila can be separated by **crossing over**.

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