Hypnotoxin in a poisonous fluid produced by

Options

A. Ascaris
B. Ants
C. parasitic protozoa
D. Nematocysts

Answer

### Step-by-Step Solution:

1. **Understanding Hypnotoxin**:
- Hypnotoxin is identified as a neurotoxin that affects nerve cells in its prey. It is a poisonous fluid.

2. **Identifying the Source**:
- The question asks where hypnotoxin is produced. It is produced in specialized structures known as nematocysts.

3. **Phylum Identification**:
- Nematocysts are found in organisms belonging to the phylum Cnidaria (often misspelled as "Nidaria"). This phylum includes jellyfish, corals, and sea anemones.

4. **Analyzing the Options**:
- The options provided include:
- Ascaris (phylum Aschelminthes)
- Ants
- Parasitic protozoa
- Nematocyst (which is associated with Cnidaria)

5. **Eliminating Incorrect Options**:
- Ascaris does not produce hypnotoxin; it is a parasitic worm with no such neurotoxin.
- Ants produce a different toxin called solenopsin, not hypnotoxin.
- Parasitic protozoa, like Plasmodium, do not produce hypnotoxin; they are parasites that invade host cells for nutrients.

6. **Conclusion**:
- The only correct option that produces hypnotoxin is the nematocyst, which is found in the phylum Cnidaria.

### Final Answer:
Hypnotoxin is produced by nematocysts found in the phylum Cnidaria.

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