Question

Which phylum do the given animals (i), (ii), (iii) and (iv) belong to?

• A. (i)- Annelida (ii)- Echinodermata (iii)- Coelenterata (iv)- Platyhelminthes
• B. (i)- Annelida (ii)- Platyhelminthes (iii)- Echinodermata (iv)- Coelenterata
• C. (i)- Platyhelminthes (ii)- Annelida (iii)- Coelenterata (iv)- Echinodermata
• D. (i)- Platyhelminthes (ii)- Annelida (iii)- Echinodermata (iv)- Coelenterata

Answer 1

The correct option is A (i)- Annelida (ii)- Echinodermata (iii)- Coelenterata (iv)- Platyhelminthes

(i) Leech belongs to Annelida- bilaterally symmetrical; body cavity is a true coelom; often divided by internal septa; has a true closed circulatory system; no true respiratory organs; reproduction normally sexual and hermaphrodite. (ii) Sea cucumber belongs to Echinodermata- radial symmetry, internal skeleton and water vascular system.

(iii) Jellyfish belongs to Cnidaria is also known as Coelenterata- diploblastic (having two embryonic layers; namely ectoderm and endoderm); radially symmetrical; generally marine; gastrovascular cavity present which opens at one end serving both as mouth and anus; the mouth is surrounded by tentacles with stinging cells called as nematocyst or cnidoblast.

(iv) Planaria belongs to Platyhelminthes- free-living; parasitic unsegmented worms that are dorsoventrally flattened; triploblastic, acoelomate, bilaterally symmetrical; organ/organ system level of organization; protonephridia as excretory/osmoregulatory structures; hermaphrodite.