Comparing Echinodermata And Mollusca

Echinodermata and Mollusca is the two common phylum in the kingdom Animalia. Echinodermata consist of five large classes which are, class Crinoidea, example feathers star, class Asteriodea, example star fish, class Ophiuroidea example, brittle star, class Echinoidea, example sea urchins and the class Holothroidea, example sea cucumber. Phylum Mollusca consist of six major classes, which are Monoplacophora, Gastropoda, Cephalopoda, Polyplacophora, Scaphopoda and the last class which is the Bivalvia.

To begin with, in Echinodermata there are four classes that will be discuss and the first class will be Ophiuroidea. Ophiuroidea is a class of the phylum Echinodermata, which brittle star is a good example of it. Ophiuroidea has loss of podial suckers,

Sea star are familiar along the shoreline where large numbers may aggregated on rocks. Sometime they cling so tenaciously that are difficult to dislodge without tearing off some tube feet. Star fish also lived on muddy or sandy bottoms and among coral reefs. They are often brightly colored and range in size from a centimetre in greatest diameter to about a meter across. Sea star has madreporite on aboral surface, they has sucker on the podia, the oral surface are against the substratum and the sea star also has the movement of anus to aboral

Bivalves are laterally compressed, and their two shells are held together dorsally by a hinge ligament that causes the valves to gape ventrally. The valves of sea clam are drawn together by adductor muscles that work in opposition to the hinge ligament. The umbo is the oldest part of the shell and growth occurs in concentric lines around it. Sea clams are commonly found in the intertidal zone, where there is a sand and mud places. Bivalvia are Byssus, they loss of radula and there shell are lateral compression of the body. The nervous system are decentralized, there head has been reduced and expansion of mantle cavity to surrounded body.

To conclude, Echinodermata and Mollusca are the two common phylum in the Animal kingdom. These are enabled and make the students to understand and clarify themselves in the difference classes and there classification in which they are belong too. It also help student to understand the different species that are belong to each classes and to identify their scientific name of each