In Echinodermata locomotion is by means of

Options

A. Muscles
B. Feet
C. Ambulacral system
D. None of the above.

Answer

**Step-by-Step Text Solution:**

1. **Understanding Echinodermata**: Echinodermata is a phylum that includes marine animals such as starfish, sea urchins, and sea cucumbers. The name "Echinodermata" means "spiny-skinned," which refers to the presence of spines on their bodies.

2. **Locomotion in Echinodermata**: The primary mode of locomotion in Echinodermata is through a unique system known as the water vascular system. This system is a characteristic feature of this phylum.

3. **The Water Vascular System**: The water vascular system consists of a network of canals filled with seawater. It includes structures called tube feet, which are essential for movement.

4. **Role of Tube Feet**: Tube feet are small, flexible appendages that extend from the body through the water vascular system. They function by using hydraulic pressure to extend and retract, allowing the organism to move along surfaces.

5. **Conclusion**: Therefore, in Echinodermata, locomotion is primarily achieved by means of tube feet, which are part of the water vascular system.

**Final Answer**: In Echinodermata, locomotion is by means of tube feet.

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