An animal has a body plan that is diploblastic, radially symmetrical and lacks a coelom. To which phylum does it likely belong?
APorifera
BCoelenterata
CPlatyhelminthes
DAschelminthes
Answer & Solution
Correct answer: B. Coelenterata
1. Diploblastic organisation is found in Coelenterata and Ctenophora only.
2. Both these phyla are radially symmetrical.
3. Coelenterates lack a coelom (they have a gastro-vascular cavity, not a true coelom).
4. So the described animal belongs to Coelenterata (Cnidaria).
_Source: syllabus Biology, Ch 4 "Animal Kingdom", §4.1_
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