CNIDARIA
Cnidarians, also known commonly as the jellyfish which is one type of cnidaria, have only one way of digesting their food. This means that food that is digested and food that is undigested leave through the same opening. This one way opening is called the Gastrovascular Cavity. Cnidarians are predators and either puncture, jab, stick to, and entrap their prey. These nematocysts inject a toxic chemical which stuns or kills their pray. Once captured, food is passed into the Gastrovascular Cavity. Nematocysts are special stinging cells.
#Notice how in the picture below, the opening in the cnidinaria (mouth) is also the opening for undigested foods (waste) to come out of.
#Notice how in the picture below, the opening in the cnidinaria (mouth) is also the opening for undigested foods (waste) to come out of.
There are two different types of cnidarian species. The medusoid shape and the polypoid shape. The medusoid shape is what we recognize as the jellyfish and their tentacles and mouths are usually pointed down. The polypoid cnidarians are in the shape of corals and they point upward and its bottom side is anchored to a colony of the same creatures. Both these cnidarians, however, digest their food the same way and their foods are alive in the digestion process.