Metamorphosis in cockroach is regulated mainly by

Options

A. corpora cardiaca
B. prothoracic glands
C. corpora allata
D. brain

Answer

**Step-by-Step Solution:**

1. **Understanding Metamorphosis:**
- Metamorphosis is the biological process by which an organism undergoes a significant change in form and structure during its life cycle. In cockroaches, this involves transitioning from nymphs to adults.

2. **Identifying the Key Players:**
- The question asks which structure regulates metamorphosis in cockroaches. The options provided are:
- Corpora cardiaca
- Prothoracic glands
- Corpora elata
- The brain

3. **Analyzing Each Option:**
- **Corpora Cardiaca:**
- These are rod-like structures located near the esophagus that secrete growth hormones. While they play a role in growth, they do not directly regulate metamorphosis.
- **Prothoracic Glands:**
- These glands are involved in the molting process (ecdysis) but are not the primary regulators of metamorphosis itself.
- **Corpora Elata:**
- This structure is crucial for metamorphosis as it secretes juvenile hormone. The presence of this hormone is essential for the larva to transition into the pupal stage. If corpora elata is removed, the larva cannot properly metamorphose and will develop into a miniature adult.
- **Brain:**
- While the brain is involved in various functions, including memory and learning, it does not play a direct role in regulating metamorphosis.

4. **Conclusion:**
- Based on the analysis, the structure that primarily regulates metamorphosis in cockroaches is the **Corpora Elata**.

**Final Answer:**
Metamorphosis in cockroach is regulated mainly by **Corpora Elata**.

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