Chitinous

... Moss animals Moss animals, sea mats Lophophore, no pedicle, ciliated tentacles about 5,000 living species Chaetognatha Longhair jaw Arrow worms Chitinous spines either side of head, fins about 100 modern species Chordata Cord Chordates Hollow dorsal nervous chord, notochord, pharyngeal slits, ...

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In an attemp to try an explan how the adaptation of an endoskeleton have increased the evolotionary success of the organisms that posses them, my text book gave the following reasons : Although stiffness provides support for muscles, exoskeleton is not as strong as an endoskeleton Endoskeleton does ...

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