Hard calcium carbonate structures are used as skeleton by (a) Echinodermata (b) Protochordata (c) Arthropoda Nematoda
ScienceClass 9CBSEAnswered 27 Mar 2026
Answer
- Soln:
- Echinodermata Explanation:
Echinodermata are spiny skinned organisms which are exclusively free-living marine animals. They are triploblastic and have a coelomic cavity. They use a unique water-driven tube from moving and they contain calcium carbonate structres which are used as skeleton.
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