Concept:Classification of animal phyla based on body symmetry, coelom, digestive system, notochord, and thermoregulation.
Key Fact:Platyhelminthes have an incomplete digestive system.
Aschelminthes possess a pseudocoelom.
In adult echinoderms, symmetry is radial (bilateral only in larvae).
Notochord persists throughout life in class Chondrichthyes.
Reptiles are poikilothermic (cannot maintain constant body temperature).
Explanation:Statement A is correct: Platyhelminthes have an incomplete digestive system.
Statement B is incorrect: Adult echinoderms exhibit radial symmetry, not bilateral; bilateral symmetry is seen only in larvae.
Statement C is correct: Aschelminthes are characterized by a pseudocoelom.
Statement D is correct: In Chondrichthyes (cartilaginous fishes), the notochord persists throughout life.
Statement E is incorrect: Reptiles are cold-blooded (ectothermic) and cannot maintain a constant body temperature; only birds and mammals are warm-blooded.
Thus, only statements B and E are incorrect.
Answer:B. B and E only
