Ampullae

Definition

Ampullae are small, bulbous structures found in echinoderms, such as starfish and sea urchins. They play a crucial role in the function of the water vascular system, aiding in locomotion and feeding.

5 Must Know Facts For Your Next Test

1. Ampullae are connected to tube feet and help control their movement by regulating water pressure.
2. They operate through hydraulic pressure changes facilitated by the contraction and relaxation of muscles.
3. Ampullae store water from the radial canals, which they then use to extend or retract tube feet.
4. The ampullae-tube foot system allows echinoderms to adhere to surfaces and capture prey.
5. Damage to ampullae can impair an echinoderm's ability to move and feed effectively.

Review Questions

• What is the primary function of ampullae in echinoderms?
• How do ampullae contribute to the locomotion of starfish?
• Describe how ampullae interact with tube feet in maintaining water pressure.

Related terms

Tube Feet: Hollow, flexible appendages used by echinoderms for movement and feeding, controlled by the water vascular system.

Water Vascular System: A network of hydraulic canals unique to echinoderms that facilitates movement, feeding, and gas exchange.

Radial Canal: A channel within the water vascular system that runs along each arm of an echinoderm and connects to individual ampullae.