What is the difference between sessile and moving?

sessile organisms remain in one place, while moving organisms are mobile. Most of the organisms are movable, but many important organisms, including corals, fungi, barnacles, tunicates, bryozoan, polycháte worms, some bivalves, and most brachiopods sit them. Of course, all land plants remain in one place. Some animals have moving larval stages and sessile phases of adults, or vice versa.

Animals that remain in place must use passive feeding methods, namely filter feeding. Substained plants use photosynthesis for energy in all rare cases. The animals have developed a number of interesting means for obtaining nutrients from the water, where they almost always live: tentacles, filters and pumps. Motile animals, which are by far the most common and popular, have a much larger number of food available to obtain food, but at the same time their nutrient requirements are larger.

Subsequently sewage organisms are from the dawn of MulticellExtremely common Life. Most of the first animals, which form a assembly called Ediacaran Fauna, were sitting. During the Ordovice period, about 480 million years ago, there was a jump in the number of filter feeding organisms, suggesting that the concentration of small sea animals (plankton) became more abundant during this period. Animals from Cambrian were almost mostly lower gadgets or predators.

Organisms that remain in one place need some effective way to protect themselves from predators - they can't swim away. It usually consists of structural elements made of chemicals, such as calcium carbonate or silica oxide, or for plants, lignin (bark). The choice tools are shells and non -nematocyst (stinging cells) that are popular among Cnidarians (as corals) and the first among others. Some of the animals like the pompeii worm that is located around the VolcaniceHoles on the seabed, place a long tube around you as they grow and are able to withdraw. The values ​​are one of the few sessile organisms without apparent defense mechanisms, except for their low nutritional value and lance (spikes) made of calcium or silica carbonate.