In which phylum is water vascular system found

Options

A. Protozoa
B. Arthropoda
C. Porifera
D. Echinodermata

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the phylum in which the water vascular system is found.

2. **Analyzing the Options**: We need to evaluate each of the provided options to determine which one contains the water vascular system.

3. **Evaluating Protozoa**:
- Protozoa are unicellular organisms and do not possess a water vascular system. They lack complex systems for water movement.
- **Conclusion**: Protozoa is not the answer.

4. **Evaluating Arthropoda**:
- Arthropods have an open circulatory system and do not have a water vascular system. They use other means for movement and respiration.
- **Conclusion**: Arthropoda is not the answer.

5. **Evaluating Porifera**:
- Porifera, or sponges, have a canal system for water movement, but this is not classified as a water vascular system. Their water movement is primarily through tiny pores called ostia.
- **Conclusion**: Porifera is not the answer.

6. **Evaluating Echinodermata**:
- Echinoderms, such as sea stars and sea urchins, possess a water vascular system. This system is a hydraulic mechanism that aids in locomotion, feeding, and respiration.
- **Conclusion**: Echinodermata is the correct answer.

7. **Final Answer**: The phylum in which the water vascular system is found is **Echinodermata**.

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