Animal Kingdom Question 21

21. Which one of the following groups of animals is bilaterally symmetrical and triploblastic?

[2009]

(a) Aschelminthes (round worms)

(b) Ctenophores

(c) Sponges

(d) Coelenterates (Cnidarians)

Show Answer

Answer : a

Hints & Solutions

(a) Aschelminthes is bilaterally symmetrical and triploblastic. These are mostly aquatic, free living or parasitic. Their body is three layered which is ectoderm, mesoderm and endoderm.