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All About Sponges

#ngscience #sponges #porifera Sponges are some of the world’s oldest and simplest animals. They are multicellular organisms, but do not have body parts, tissues or organs. Their asymmetrical bodies consist of one or more tubes with an opening at the top. An asymmetrical body does not have any lines of symmetry. Most sponges live in the ocean, but some live in fresh water environments. Sponges are filter-feeders. They pump sea water through the holes in their bodies called pores. As water moves through the pores, bacteria and tiny particles are taken up from the water as food. Sponges do not move about and rely on a continual flow of water through their bodies to obtain food and oxygen and to remove wastes. Sponges usually reproduce sexually, but some reproduce asexually by budding. Budding is the process in which a new organism develops from an outgrowth on the body of the parent organism. Once developed, the offspring detaches as a new organism that is genetically identical to its parent. Hey! Want to know something really interesting about sponges? They're hermaphrodites! This means they can function as both sexes - male and female - simultaneously!. During sexual reproduction, male sperm cells are released into the water. The sperm cells enter other sponges and fertilize female eggs cells. The egg cells develop into free-swimming larvae and are released into the water. The larvae eventually find a place to settle and attached themselves to the sea floor and the lifecycle of these strange and simple animals continues.