Paedomorphosis occurs in

Options

A. Oikopleura
B. Salpa
C. Balanoglossus
D. Branchiostoma

Answer

**Step-by-Step Solution:**

1. **Understanding Paedomorphosis**:
- Paedomorphosis is a biological phenomenon where an organism retains juvenile or larval characteristics into its adult life. This can occur in various species, particularly in certain chordates.

2. **Analyzing the Options**:
- The options provided are Oikoplura, Salpa, Belanoglossus, and Branchiostoma. We need to determine which of these organisms exhibits paedomorphosis.

3. **Identifying Oikoplura**:
- Oikoplura is a type of pelagic tunicate. It is known for its unique life cycle, which includes the retention of larval features into adulthood, making it a prime example of paedomorphosis.

4. **Examining Other Options**:
- Salpa: This is another type of tunicate, but it does not exhibit paedomorphosis.
- Belanoglossus: This organism, also known as the acorn worm, does not show paedomorphosis.
- Branchiostoma: This is a lancelet, which retains some primitive features but does not exhibit paedomorphosis in the same way as Oikoplura.

5. **Conclusion**:
- Based on the analysis, the organism that exhibits paedomorphosis is Oikoplura. Therefore, the correct answer is Oikoplura.

**Final Answer**: Oikoplura

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