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Echinoderms are radially symmetrical animals that are only found in the sea, there are none on land or in fresh water. They
also had Radial Symmetry.
Most Enchinoderms are Carniverous. Echinoderms can regenerate missing limbs, arms, spines - even intestines (for example
sea cucumbers). Some brittle stars and sea stars can reproduce asexually by breaking a ray or arm or by deliberately splitting
the body in half. Each half then becomes a whole new animal.
Echinoderms have tentacle-like structures called tube feet with suction pads situated at their extremities. These tube
feet are hydraulically controlled by a remarkable vascular system. This system supplies water through canals of small muscular
tubes to the tube feet. As the tube feet press against a moving object, water is withdrawn from them, resulting in a suction
effect. When water returns to the canals, suction is released. The resulting motion is very slow.
Reproduction:
Regeneration
The ability of an organism to grow a body part that has been lost
Autotomy
The self amputation of an appendage when the organism is injured or under attack. The autotomized part is usually regenerated.
Budding
Is asexual reproduction in which an outgrowth on the parent organism breaks off to form a new individual
Fission
Self-division into two parts, each of which then becomes a separate and independent organisms (asexual reproduction)
Examples : Starfish
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