OESOPHAGUS STOMACH
ECHINODERMS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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TRUE, the endoskeleton is composed of soft plates.
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FALSE, the endoskeleton is composed of hard plates.
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Either A or B
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None of the above
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Detailed explanation-1: -Echinoderm skeletons are made up of interlocking calcium carbonate plates and spines. This skeleton is enclosed by the epidermis and is thus an endoskeleton. In some, such as sea urchins, the plates fit together tightly.
Detailed explanation-2: -Echinoderms have a skeleton composed of numerous plates of mineral calcium carbonate (calcite).
Detailed explanation-3: -The endoskeleton of echinoderms (Deuterostomia: Echinodermata) is of mesodermal origin and consists of cells, organic components, as well as an inorganic mineral matrix.
Detailed explanation-4: -Their bodies look like pin cushions. The sea star’s skeleton, like the sea urchin’s, is an endoskeleton consisting of small plates of calcium carbonate embedded in the epidermis. These plates, called ossicles, are much smaller than those of sea urchins.