In: Biology
Mollusca |
Annelid |
Echinoderm |
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Body Symmetry |
Bilateral symmetry. Few species do show torsion and hence loose symmetry. |
Bilateral Symmetry |
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Body Cavity |
Haemocoel |
True Coelomate |
True coelomate |
Circulatory System |
Open circulatory system where blood flows through the empty blood spaces and not in the blood vessels. Caity is called haemocoel as it is filled with blood.Single heart pumps blood to aorta and passes it to visceral mass through blood vessels. |
Annelids have closed circulatory system in which the blood flows
in network of blood vessels. There are five hearts to pump blood
towards dorsal blood vessels. Blood is collected through various
vessels like supraoesophageal etc. |
Water canal system present for circulation. All substances are transported with the water only. It enters through the madreporite and passes through ambulacral gooves in the arms that further stretches to the tube feet. |
Two special features |
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