Description
Cephalopoda is considered the most complex class of the phylum Mollusca. The name Cephalopoda comes from the greek root word kephale meaning "head" and pous or pod meaning "foot". There are about 800 identified living species of Cephalopods and they are found in all the worlds oceans, including the arctic and antarctic. All Cephalopods have the common characteristic of a chitinous beak used for consuming and crushing prey.
Physical Features
Cephalopods are bi-lateral which means that if you were to cut one down the middle, the specimen would be symmetrical. The class' most defining feature would be the tentacles that extend from their body, which can arrange from a total of 8 to 90. Cephalopods are the only mollusks with a closed circulatory system as well as a highly functioning brain. Most cephalopods have the ability to camouflage or mimic their surroundings by chromatophores under the skin that change pigment. The radula, a toothed tongue used for scrapping off bits of food, and beak of a cephalopod are used in combination to break down food for digestion. Cephalopods have a complete digestive system.