GAMNI MADAAN , Academic Content Writer at EDUMARZ
The Members of Porifera Phylum are commonly known as “sponges”’. They are marine , asymmetrical and primitive multicellular animals. They also possess a canal system.
GENERAL FEATURES ARE :–
Symmetry = They are mostly asymmetrical, rarely radial symmetrical( Leucosolenia).
Habitat = All are aquatic species generally marine.
Body organisation = They possess cellular level of organisation means ” cells are loosely arranged and independently perform their own functions without being transformed into tissues.
Canal system = They have a water transport or canal system which directly helps in food gathering , waste removal and in respiratory exchange. In this , water enters through very small pores openings called “ostia ” into a central cavity called ” spongocoel ” goes out through the “osculum”.
Skeleton = Their body is protected by a Skeleton which is made up of spicules (made up of calcium carbonate or silica ) or spongin fibres (made up of protein).
Digestion = Digestion is intracellular ( breakdown of substances within the cytoplasm of a cell).
Respiration and excretion = It occurs through the body surface of species.
Sexuality = They are hermaphrodite means sexes are not separate i.e. eggs and sperms are produced by the same organism .
Reproduction =They produce asexually by fragmentation or budding and by sexually through formation of gametes.
Fertilisation = In this , Fertilisation of an organism is internal ( means sperms are fertilised inside the female body).
Examples : Spongilla (freshwater sponge),Sycon
(Scypha) and Euspongla (Bath sponge).