Question

Features of phylum porifera

Answer 1

Answer:

They are generally marine aquatic organisms, with a few freshwater species.

Their bodies are asymmetrical.

Body shape can be cylindrical, vase-like, rounded or sac-like.

They are diploblastic animals with two layers, the outer dermal layer and the inner gastral layer.

Answer 2

Answer :

Phylum - Porifera :

• The members of phylum porifera are commonly called as sponges.
• They are asymmetrical animals.
• They are marine animals.
• They are primitive organisms.
• They are multicellular and have cellular level of organisation.
• They have a water transport system in their body.
• The water enters the body through minute pores called Ostia.
• The water then enters into the body cavity called spongocoel, and then it goes out through the osculum.
• This pathway of water transport helps this organism to collect food.
• It also helps in respiration and removal of waste.
• The cells lined up in the spongocoel are called Choanocytes.
• The skeleton is made up of spicules or spongin fibres.
• They are hermaphrodite.
• The digestion is intracellular.
• They reproduce asexually by fragmentation and sexually by formation of gametes.
• The fertilization is internal.
• The development of of new individual porifera includes a larval stage, in which the organism is morphologically different from the adult.
• Examples include : Sycon, Spongilla, etc.