Starfish to starfish by the French zoologist de Blainville in 1830. It is derived from the Greek "aster", ἀστήρ (a star) and the Greek "eidos", εἶδος (form, likeness, appearance). The class Asteroidea belongs to the phylum Echinodermata. As well as the starfish, the echinoderms include sea urchins, sand dollars, brittle and basket stars, sea cucumbers and crinoids. The larvae of echinoderms have bilateral symmetry, but during metamorphosis this is replaced with radial symmetry, typically pentameric. Adult echinoderms are characterized by having a water vascular system with external tube feet and a calcareous endoskeleton consisting of ossicles connected by a mesh of
Alternatives to animal testing performed on intact animals, the maintenance of cells in culture normally requires the use of animal-derived serum. Although exact figures are difficult to obtain, some have estimated that one million fetal cows are sacrificed each year to obtain the world's supply of fetal bovine serum, used to grow cultured cells. Skin irritation and skin corrosion refer to localized toxic effects resulting from a topical exposure of the skin to a substance. Human skin equivalent tests can be used to replace animal-based corrosive and irritative studies. EpiDerm from Mattek and EpiSkin and SkinEthic RHE model are derived from human skin cells