In Cockroach moulting is induced by secretion of

Options

A. Prothoracic gland
B. Corpora allata
C. Corpora cardiaca
D. Neurosecretory cells

Answer

**Step-by-Step Solution:**

1. **Understanding Moulting in Cockroaches**: Moulting, also known as ecdysis, is a process where an insect sheds its exoskeleton to allow for growth. In cockroaches, this process is regulated by hormones.

2. **Role of Neurosecretory Cells**: When a cockroach grows and requires a larger exoskeleton, sensory inputs from the body activate neurosecretory cells located in the brain.

3. **Secretion of Brain Hormone**: These activated neurosecretory cells secrete a hormone known as the brain hormone, which is crucial for initiating the moulting process.

4. **Activation of Corpora Cardiaca**: The brain hormone triggers the corpora cardiaca, which is a structure that stores neurosecretory products. This structure releases a hormone called PTTH (prothoracicotrophic hormone) into the circulatory system.

5. **Stimulation of Prothoracic Glands**: The sudden release of PTTH stimulates the prothoracic glands to secrete the moulting hormone.

6. **Conclusion**: Therefore, the secretion that induces moulting in cockroaches primarily comes from the prothoracic glands.

**Final Answer**: In cockroaches, moulting is induced by the secretion of the prothoracic gland.

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