Filum echinodermata pdf
Tropical echinoderms are primarily epibenthic fauna and a prominent element of many shallow reefs. Echinoderms are exclusively marine deuterostomes with about described living and roug extinct species. All the animals in Phylum Echinodermata exhibit spiny skin and hence are grouped together. Echinodermata are so named owing to their spiny skin (from the Greek “echinos” meaning “spiny” and “dermos” meaning “skin”), and this phylum is a collection of about 7,000 described living species. Sea urchins (Echinoidea) are Echinoderms filum that is a group of a soft-shelled animals and lack of the backbone.
Echinodermata is a phylum of many unique and beautiful sea creatures which all share a set of common defining traits. Echinoidea has the characteristics of thorns which can be used as one of the characters in identification and classification. They are unique among Bilateria for the secondary pentaradial symmetry of their body. Phylum Hemichordata is a small phylum with only a 100 known species, with animals having a worm-like appearance. Classification of Phylum Echinodermata: Phylum Echinodermata is divided into five classes.
An interesting feature of the phylum Echinodermata is that all the organisms belonging to this phylum are marine. From these resemblances, it is clearly proved that the Echinoderms are nearer to the Chordates than any other group. Echinodermata has approximately 7000 described living species and about 13,000 extinct species known from the fossil record. It also indicates that the chordates have been evolved from Echinoderm-like ancestors. This research applies model of ADDIE (Analysis, Design, Development, Implementation, Evaluation). Phylum Echinodermata The Phylum Echinodermata is made up of the most advanced invertebrates and includes organisms such as the starfish, sea urchins and sea cucumbers. The water vascular system present in echinoderms accounts for gaseous exchange, circulation of nutrients and waste elimination. Sea urchins often present in large numbers, especially in sandy, algal bed areas.
The word echinoderm means spiny skin (echino = spiny, derm = skin) which is fitting; their endoskeleton is composed of calcium-based plates called ossicles that are covered by a thin skin.