Most sponges are anchored to hard surfaces like rocks, but some sponges can attach themselves to soft sediments using a root-like base. How do sponges attach themselves to a surface? Juveniles drift or swim freely, while adults are stationary. Although adult sponges are fundamentally sessile animals, some marine and freshwater species can move across the sea bed at speeds of 1–4 mm (0.039–0.157 in) per day, as a result of amoeba-like movements of pinacocytes and other cells. They number approximately 5,000 described species and inhabit all seas, where they occur attached to surfaces from the intertidal zone to depths of 8,500 metres (29,000 feet) or more. Sponge, any of the primitive multicellular aquatic animals that constitute the phylum Porifera. These cells interconnect and form a network over the entire animal. The bud attaches to a surface where it grows into an adult. What attaches a group of sponge to a surface?Ī bud breaks off an adult sponge. One end is attached to a solid such as a rock while the other end, called the osculum, is open to the environment. Their walls are lined with many small pores called ostia that allow water flow into the sponge. They don’t have muscles, a nervous system, or a circulatory system. They stay put in one place stuck to the bottom of the water- either salt or fresh. Like plants they do not move, i.e., they are sessile. This misconception is due to some of the characteristics of the Porifera (Dawkins 2004). People often think of sponges as plants, rather than being animals. 8 Where are the sponge cells located in the body?.7 What kind of organism is permanently attached to the ground?.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |