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.