The frequency of crossing over between any two linked genes is

Options

A. Higher if they are recessive
B. Determined by their relative dominance
C. The same as if they were not linked
D. Directly proportional to the distance between them

Answer

To solve the question regarding the frequency of crossing over between any two linked genes, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Crossing Over**:
- Crossing over is a process that occurs during meiosis where homologous chromosomes exchange genetic material. This process contributes to genetic diversity.

2. **Identifying Linked Genes**:
- Linked genes are genes that are located close to each other on the same chromosome. Their proximity affects the likelihood of crossing over occurring between them.

3. **Frequency of Crossing Over**:
- The frequency of crossing over between two linked genes is influenced by the distance between them on the chromosome.

4. **Relationship Between Distance and Frequency**:
- The closer two genes are to each other, the lower the probability of crossing over occurring between them. Conversely, the farther apart they are, the higher the probability of crossing over.

5. **Conclusion**:
- Therefore, the frequency of crossing over between any two linked genes is **directly proportional to the distance between them**.

### Final Answer:
The frequency of crossing over between any two linked genes is directly proportional to the distance between them.

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