What is Porifera?
Those animals which are attached with the substratum in water, multi-cellular but without any organ systems and poses numerous minute apertures with various types of canals in the body are include in the phylum Porifera. The term porifera is formed by two Latin words; those are ‘porus’ which means the aperture and ‘ferre’ which means to bear. All these animals are commonly known as sponges. Sponges are aquatic animals. Their body contains numerous minute apertures or pores. They are all pore bearing animals and hence the name of the phylum is Porifera. Members of phylum porifera are considered as parazoa , due to the presence of cellular grade of the body organisation and lack of tissue grade of the body pattern.
Some Characteristic Features of Porifera:-
i) All species of phylum porifera are living in aquatic medium. Generally they are marine liver but animals of the spongillidae family are living in sweet or fresh water.
ii) Porifera are solitary or colonial.
iii) Adult porifera sponges are attached with some submerged material on the substratum of water.
iv) They cannot move from one place to another but their larval stage can swim in water.
v) Varieties of sponges are with branches and sub-branches just like the plants.
vi) Porifera possess ostia, canal system and osculum. Large number of minute microscopic pores is distributed on the outer surface of the body and these pores are known as Ostia.
vii) On the body and body wall there are various types of canals in porifera that are collectively known as canal system.
viii) Water from the outside, enters to the body through ostia and this water flows to the body through the canal system and the water eliminates to the outside of the bodyfrom the terminal part called the Osculum.
ix) The body of porifera is made up of many cells which are loosely arranged into two layers in the body and jelly like mesenchyme is present between the two cell layers.
x) Organ system as well as nervous tissue are absent in the body of sponges.
xi) Flagellated choanocytes are present in their layer of the body. This type of cells present only in the sponges among the metazoan group.
xii) Very high regenerative capacity is present in the sponges.
xiii) Innumerable number of minute pointed spicules and spongian fibres are present in the mesenchyme and they form the frame-work of the body.
xiv) Sexual and asexual, both types of reproductive processes are present in the sponges. In sexual reproduction, internal fertilization takes place and in the cases of asexual reproduction it is occurs by budding process.
What is the importance of Poriofera?
From the prehistoric time man are using sponges variously. Spongia, Euspongia like sopngesare utilizedfor the production of commercial sponge. Sopgnes are used for cleaning floor, wall, car, furniture, computer, mechinaries and the jhuman bodies. They are also used in various other productions also.So the porifera has its greet importance in in mankind for its domestic, commercial and industrial uses.