Characteristics
- Echinoderms are characterized by their radial symmetry, several arms radiating from a central body.
- The body consists of five equal segments, each containing a duplicate set of various internal organs.
- They have no heart, no brain, and no eyes, but some brittle stars have light sensitive parts on their arms.
- They have tentacle like structures called tube feet with suction pads situated at their extremities.(edges)
- These tube feet are hydraulically controlled by a remarkable vascular system.
- Echinoderms are characterized by their radial symmetry, several arms radiating from a central body.
Subgroups of Echinoderms
These are the types/ subgroups of echinoderms and what they are called......
Asteroids: (sea stars)
Crinoidea: (feather stars and sea lilies)
Echinoidea: (sand dollars and sea urchins)
Holothuroidea: (sea cucumbers)
Ophiuroidea: (brittle stars)
Asteroids: (sea stars)
Crinoidea: (feather stars and sea lilies)
Echinoidea: (sand dollars and sea urchins)
Holothuroidea: (sea cucumbers)
Ophiuroidea: (brittle stars)