17.The presence of pores in Porifera is called__. [A] cnidoblasts [B] Ostia [C] Medusa [D] None of these Show Answer
The pores on Sponges' bodies are ostia. Sponges contain many pores on their bodies, which enable water to enter. In some sponges, ostia are formed by porocytes, which are solitary tube-shaped cells that act as valves to regulate the flow of water into the spongocoel.
