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The terms venom and poison are often used interchangeably. Although both venomous and poisonous animals have potentially dangerous toxins in their bodies, the way that toxin is delivered differs. Venomous animals have an active delivery system and may use their ....

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.... of the phylum Echinodrmata, having external skeletons of calcareous plates just under the skin, no head, and a water vascular-system with tube feet. Echinoderms are radially symmetrical, lack specialized ecretory organs, and reproduce sexually. Echinoderms have the ability to regenerate lost or injured body parts. Starfish: Starfishes are free-living echinoderms that have a flat, star-shaped or pentagonal body, usually with a continuous disc that has five or more ray-like extensions called arms. Tube feet are located in an open furrow along the underside of the arms. These arms contain the digestive glands and genital organs. Located on the up ....