OESOPHAGUS STOMACH
ECHINODERMS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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bilateral symmetry
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water-vascular system
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internal skeleton
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nonsegmented body
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Detailed explanation-1: -Enterocoelom is a type of true coelom. Echinoderms and chordates have Enterocoelom.
Detailed explanation-2: -Similarities Between Echinoderms and Chordates They show bilateral symmetry at any stage of their life cycle. Therefore, they belong to the clade Bilataria. Also, both are deuterostomes whose blastopore develops into the anus. And, both exhibit radial cleavage, which is indeterminate.
Detailed explanation-3: -Echinoderms have an internal skeleton made of bony plates (ossicles) of calcium carbonate. They deposit this material after extracting dissolved calcium and carbonate (bicarbonate) ions from sea water. In some species, such as the sea urchin, plates of the skeleton are locked together to form a rigid structure.
Detailed explanation-4: -Echinoderms have an internal skeleton (endoskeleton) made of calcareous or bony plates called ossicles. These are the first animals we have studied that have endoskeletons Note that these endoskeletons are of mesodermal origin 4. The echinoderm body is covered by calcareous spines.