Q. A digestive system with a single opening that serves as both mouth and anus is called incomplete and is found in:
A) Aschelminthes
B) Platyhelminthes
C) Annelida
D) Echinodermata
Explanation
Flatworms have an incomplete digestive system. Aschelminthes, Annelida and Echinodermata have complete alimentary canals with separate mouth and anus.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.