Balbiani rings occur in

Options

A. Lampbrush chromosome
B. Heterosome
C. Allosome
D. Polytene chromosome

Answer

**Step-by-Step Solution:**

1. **Understanding Balbiani Rings:**
- Balbiani rings are defined as large chromosome puffs that are found on certain chromosomes. They are important for the transcription of RNA.

2. **Identifying the Chromosome Type:**
- These rings are specifically associated with polytene chromosomes. Polytene chromosomes are characterized by having multiple DNA strands and are typically found in the salivary gland cells of organisms like fruit flies.

3. **Analyzing the Options:**
- The options given are:
1. Lambrusch chromosome
2. Heterosome
3. Allosome
4. Polytene chromosome

4. **Evaluating Each Option:**
- **Lambrusch Chromosome:** This type of chromosome is found in growing oocytes and does not contain Balbiani rings. Therefore, this option is incorrect.
- **Heterosome:** Heterosomes are not associated with Balbiani rings, making this option incorrect as well.
- **Allosome:** Allosomes refer to sex chromosomes, which do not exhibit Balbiani rings. Hence, this option is also incorrect.
- **Polytene Chromosome:** This is the correct option as Balbiani rings are indeed found on polytene chromosomes.

5. **Conclusion:**
- The correct answer to the question "Balbiani rings occur in" is the **Polytene chromosome**.

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