OESOPHAGUS STOMACH
ECHINODERMS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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True
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False
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Either A or B
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None of the above
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Detailed explanation-1: -The echinoderms have endoskeleton made of calcareous ossicles. All echinoderms are exclusively marine.
Detailed explanation-2: -Echinoderms are exclusively marine organisms with spiny bodies. They have an endoskeleton rich in calcium, basically made of calcareous ossicles.
Detailed explanation-3: -Although these spines may look like components of an exoskeleton at first glance, echinoderms do not have an exoskeleton. Instead, the spines are extensions of an internal endoskeleton. The endoskeleton is composed of calcium carbonate plates and spines that are actually covered by a thin layer of epidermis (skin).
Detailed explanation-4: -Echinoderms do not have an exoskeleton. The skeleton of echinoderms is composed of calcium carbonate plates that are enclosed or covered by a thin layer of skin (epidermis) and supported by the mesodermal tissue and therefore, this is an endoskeleton.
Detailed explanation-5: -Echinoderms are triploblastic. Echinoderms have spiny skin. Unio is a mollusc.