Explanation: Class Cephalopoda are highly advanced and organized group of marine animals that have a distinctive characteristics of their head been attached to their body and they possess tentacles that is to say their head is completely merged with their foot with their arms or tentacles surrounding the head.
Their body plan includes the head, two eyes, a mantle, a siphon and a minimum of eight arms. Some examples are octopus, squid and the cuttlefish
primary division of the sea, which includes the whole mass of water subdivided into neritic and oceanic zones; also pertaining to the open sea (open water)
