The poisonou fluid present in the nematocyctes of hydra is

Options

A. haemoglobin
B. venom
C. haematin
D. hypnotoxin

Answer

**Step-by-Step Solution:**

1. **Identify the Organism**: The question refers to Hydra, which belongs to the Phylum Cnidaria. This is important to understand the context of the question.

2. **Understand Nematocysts**: Nematocysts are specialized stinging cells found in Cnidarians, including Hydra. They serve as both a defense mechanism and a means to capture prey.

3. **Explore the Function of Nematocysts**: Nematocysts contain a poisonous fluid that is injected into prey or potential threats when the nematocyst is triggered.

4. **Evaluate the Options**: The question provides several options for the poisonous fluid:
- Hemoglobin: Found in vertebrate blood, not in Hydra.
- Venom: Generally associated with snakes and other chordates, not applicable to Hydra.
- Hematin: A component related to hemoglobin, not relevant to Hydra's nematocysts.
- Hypnotoxin: This is a toxin found in the nematocysts of Hydra, responsible for immobilizing prey and providing defense.

5. **Select the Correct Answer**: Based on the evaluation, the correct answer is Hypnotoxin, as it is the poisonous fluid present in the nematocysts of Hydra.

**Final Answer**: The poisonous fluid present in the nematocysts of Hydra is Hypnotoxin.

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