Q. The skeleton of sponges is made up of:
A) Calcium carbonate skeleton as in corals
B) Chitinous exoskeleton
C) Spicules or spongin fibres
D) Calcareous ossicles
Explanation
Porifera have a skeleton of spicules or spongin fibres. Corals (cnidarians) have a calcium carbonate skeleton, arthropods a chitinous exoskeleton and echinoderms calcareous ossicles.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.