Water vascular system helps in

Options

A. locomotion
B. capture and transport of food
C. respiration
D. all of the above

Answer

**Step-by-Step Solution:**

1. **Identify the Phylum**: The water vascular system is a unique feature found in members of the phylum Echinodermata. This includes organisms such as starfish, sea urchins, and sea cucumbers.

2. **Understand the Function**: The primary function of the water vascular system is to facilitate locomotion. It allows echinoderms to move by using hydraulic pressure to extend and retract their tube feet.

3. **Mechanism of Action**: The water vascular system consists of a network of fluid-filled canals. Water enters the system through a structure called the madreporite, and it is then distributed throughout the body, allowing the tube feet to operate.

4. **Additional Functions**: Besides locomotion, the water vascular system also plays a role in feeding and gas exchange, but its main contribution is to movement.

5. **Conclusion**: Therefore, the water vascular system is essential for locomotion in echinoderms, enabling them to navigate their aquatic environments effectively.

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