Question

What are the functions of sponges' specialized cells: archaeocytes, choanocytes, porocytes?

Answer 1

Sponges are the group of organisms that are the members of phylum Porifera which means the pore bearing organisms. They are multicellular organisms that are aquatic and invertebrates. They have specialised cells which help them in surviving the environment where they thrive.

Complete answer:
Sponges are aquatic invertebrates that are found in marine as well as freshwater. They are mostly found attached to the surfaces of the rocks. The sponges can be asymmetrical or radially symmetrical which are found in a variety of shapes. Their move may have spicules or calcareous outer covering. They are heterotrophic and do not have cell walls. They do not have true organs and tissues. They also have certain specialised cells which help them to live in water. They are-

Archaeocytes- These are the kind of ameboid cells present in the sponges. These cells are present in the mesohyl of the sponges. They are mainly the totipotent cells that can transform into other cells in the sponges. They also play an important role in nutrition and reproduction in sponges. They also help in forming spicules.

Choanocytes- They are also known as collar cells. They have flagella which help in filtering particles from the water. The beating of flagella creates a water current which helps in absorbing the food particles. It also serves as a system of digestion.

Porocytes- These are the tube-like cells that make up the pores of the sponges called the Ostia. It controls the amount of water entering inside the sponges. These cells have the capacity to contract in harsh environments.

Note: The choanocytes and porocytes helps in feeding. Pinacocytes are the specialised cells present in the sponges. They help in cell adhesion, movement, phagocytosis, signalling and polarity. It helps in maintaining the shape of the sponge.