Porifera: Structure and Functions

Study Notes

Members of this phylum are commonly known as sponges.
They are generally marine and mostly asymmetrical animals.
They are primitive multicellular animals with a cellular level of organisation.
They have a water transport or canal system that brings in water through minute pores (ostia) in the body wall into a central cavity, spongocoel.
Water then exits through the osculum, facilitating food gathering, respiratory exchange, and removal of waste.
The spongocoel and canals are lined with choanocytes or collar cells.
Digestion in sponges occurs at the intracellular level.

The body of a sponge is supported by a skeleton made up of spicules or spongin fibres.

Sponges are hermaphrodites, producing both eggs and sperms in the same individual.
They reproduce asexually by fragmentation and sexually by formation of gametes.
Fertilisation is internal and development is indirect, involving a larval stage that is morphologically distinct from the adult.

Members of this phylum are commonly known as sponges.
They are generally marine and mostly asymmetrical animals.
They are primitive multicellular animals with a cellular level of organisation.
They have a water transport or canal system that brings in water through minute pores (ostia) in the body wall into a central cavity, spongocoel.
Water then exits through the osculum, facilitating food gathering, respiratory exchange, and removal of waste.
The spongocoel and canals are lined with choanocytes or collar cells.
Digestion in sponges occurs at the intracellular level.

The body of a sponge is supported by a skeleton made up of spicules or spongin fibres.

Sponges are hermaphrodites, producing both eggs and sperms in the same individual.
They reproduce asexually by fragmentation and sexually by formation of gametes.
Fertilisation is internal and development is indirect, involving a larval stage that is morphologically distinct from the adult.