In most sponges, however, larvae (LAR-vee) develop inside the female's body and are born alive through the sponge's water-exit hole. Others are treelike or bushy. Others are fan shaped. Licence Data provider Data resource. SPONGES: PoriferaNO COMMON NAME (Soleneiscus radovani): SPECIES ACCOUNTSBIRD'S NEST SPONGE (Pheronema carpenteri): SPECIES ACCOUNTSFRESHWATER SPONGE (Spongilla lacustris): SPECIES ACCOUNTS Source for information on Sponges: Porifera: Grzimek's Student Animal Life Resource dictionary.
2. This type of canal system is found in Geodia and Stelleta. 7. The interior space of sponge body is called spongocoel. The basal wall is termed the hypophare which is devoid of flagellated chambers. Asconoid sponges with radially symmetrical cylindrical body. 13. Other amoebocytes divide to produce a large number of sperms, a sperm has an oval head and a long tapering tail. They are cylindrical or funnel-shaped and are found in deep tropical seas, they grow up to one metre. 10. Sexual reproduction occurs by ova and sperms; fertilisation is internal but cross- fertilisation occurs as a rule. 2. 5. The canal system also increases the surface area of the sponges in contact with the water and, thus, enables the sponges to increase their volume as surface volume ratio must remain fixed. This embryo attaches itself to some solid object by its blastoporal end and it begins to grow. The regeneration power is used for cultivation of bath sponge industrially. The current of water which flows through the canal system brings the food and oxygen and takes away the carbon dioxide, nitrogenous wastes and faeces. Microscleres are absent. A pumping action moves the water through the sponge and out through a large hole at the end of each tube. For a long time sponges were not regarded to be animals, exactly because of their non- animal-like appearance; they are sessile and do not possess the ability to catch the food or getting rid of their wastes and exhibit more or less no response to stimuli. A few sponges, however, are carnivorous (kar-NIH-vuh-rus), or meat eating. 1. The parenchymula larva of sponges are comparable with the planula of coelenterates. Monaxon megascleres are of only one type, viz., diactinal. Absence of digestive cavity and presence of intracellular digestion. It is formed by the out-pushing of the wall of an asconoid sponge at regular intervals into finger-like projections, called radial canals. Only a few sponges are harmful. Amphidiscs are straight rods with thorny sides and a ring of hooks at each end. Then, copy and paste the text into your bibliography or works cited list. Monaxon megascleres in the form of tylostyles. Many sponges live on reefs. The nature of sponges was debated until well into the nineteenth century, although evidence of their animal nature was given in 1765 by who saw the water currents and movements of the oscula. Syconoid or leuconoid sponges having vase- shaped body. Another very unusual method of asexual reproduction is the formation of reduction bodies. Scientific Names of Plants to the Rescue! Source: Wikipedia . According to Hyman, the important features of the asconoid structure are the simple wall and the complete continuous lining epithelium of choanocytes, interrupted only by the inner ends of the porocytes. The uninucleate archeocytes remain embryonic.
The relation of the flagellated chambers to the incurrent canals remain as before. The skeleton may be of spongin fibres or of spongin fibres with siliceous spicules or there may be no skeleton. They may show asconoid, syconoid, or leuconoid structure. There are usually three types of canal system met within sponges, viz-, asconoid type, syconoid type and leuconoid type. ; some are boring sponges like Cliona. The nature of sponges was debated until well into the nineteenth century, although evidence of their animal nature was given in 1765 by who saw the water currents and movements of the oscula. http://www.pgc.nrcan.gc.ca/marine/sponge/index_e.htm (accessed on January 21, 2005). The flagellated sponge larva are considered as the remnant of some flagellated colonial protozoan ancestor. 1. Spicules are distinguished into megascleres and microscleres. Spicules are not differentiated into megascleres and microscleres.