Pick 3 invertebrates Compare them in terms of physical features and systems. Identify at least 3 similarities and 3 differences.

Abalone
The abalone has a flattened spiral shell that protects the muscular foot. Abalones are permanently attached to their shell by the muscle attachment. It also has holes on the edge of the shell that release eggs or sperm, discharge metabolic wastes and allow water to flow out after passing through the animal's gill chamber. The abalone feeds by clinging onto rocks, waiting for a piece of kelp to drift by. It then clamps down on the kelp with its foot and chews on it with its radula- a rough tongue with many small teeth.


Starfish
The starfish has arms attached to the body. Under the bottom of the starfish are tube feet that help with movement and feeding. The starfish has a water vascular system.