Q. What is the correct pathway of water flow through the canal system of a sponge?
A) Osculum → spongocoel → ostia
B) Ostia → osculum → spongocoel
C) Spongocoel → ostia → osculum
D) Ostia → spongocoel → osculum
Explanation
Water enters through minute pores (ostia) into the central cavity (spongocoel) lined by choanocytes and leaves through the osculum. This helps in food gathering, respiratory exchange and waste removal.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.