![]() ![]() There are three classes of sponges existing now: Demospongiae, Calcarea and Hexactinellida (other classes have become extinct and are found in the fossil record). Sponges occur in marine and freshwater but do not occur on land. Sponges exist in all different shapes, sizes and colours, and members of the same species can vary depending upon where they live. This passage of water also brings in oxygen and takes out carbon dioxide and wastes. They feed by pumping large quantities of water (hundreds of litres per day) through their bodies and filtering out tiny organisms and dead plant and animal particles as food. How do sponges feed Specific cells within the sponge have what are known as ‘flagella’. The larvae are able to move through the water and settle once they find a suitable substrate to grow into an adult sponge. As a result, they are unable to move to escape predators, but discourage attack with strong chemicals and an exterior of bristly textures. The egg develops inside the sponge until being released as a larva. Sponges are sessile animals, they live permanently affixed at the base and do not move around as adults. Their skeleton can be composed from two materials: spongin (a soft, flexible organic material - made of the protein collagen) and spicules (small rods of calcium carbonate or silica). They are considered simple animals as they consist of many cell types with special functions and they lack tissues and organs. ![]() Porifera means "pore bearer" and is the scientific name for sponges. Photo by Clay Bryce, image copyright WA Museum ![]() Collection Highlights | Updated 10 years ago Sarcotragus sp. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |