phylum – porifera - samagra.itschool.gov.in · euspongia (bath sponge) 00 osculum os ia...

PHYLUM – PHYLUM –

PORIFERAPORIFERA

● Cellular level of organisationCellular level of organisation● AsymmetricalAsymmetrical● AcoelomateAcoelomate● DiploblasticDiploblastic

HABIT AND HABITATHABIT AND HABITAT

● Generally marine. Generally marine. ● Commonly known as Commonly known as spongessponges..

Water transport or canal Water transport or canal systemsystem

● Ostia → spongocoel → Ostia → spongocoel → osculumosculum

● Water enters through minute Water enters through minute pores (ostia) in the body wall pores (ostia) in the body wall into a central cavity, into a central cavity, spongocoel, from where it goes spongocoel, from where it goes out through the osculum. This out through the osculum. This pathway of water transport is pathway of water transport is helpful in food gathering, helpful in food gathering, respiratory exchange and respiratory exchange and removal of waste. removal of waste.

● Choanocytes or collar cells line the spongocoel and the canals.

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

REPRODUCTIONREPRODUCTION

● HermaphroditeHermaphrodite – sexes are not – sexes are not separate (eggs and sperms are separate (eggs and sperms are produced by the same individual)produced by the same individual)

Asexual – fragmentation Asexual – fragmentation

Sexual – gametes

LIFE HISTORY ● Indirect development

Has a larval stage which is morphologically different from the adult.

SYCONSYCON ((SCYPHASCYPHA))

SPONGILLASPONGILLA (FRESH WATER SPONGE)(FRESH WATER SPONGE)

EUSPONGIA (BATH SPONGE)