Cephalopod eight or ten. Decapods such as cuttlefish and squid have five pairs. The longer two, termed "tentacles", are actively involved in capturing prey; they can lengthen rapidly (in as little as 15 milliseconds). In giant squid they may reach a length of 8 metres. They may terminate in a broadened, sucker-coated club. The shorter four pairs are termed "arms", and are involved in holding and manipulating the captured organism. They too have suckers, on the side closest to the mouth; these help to hold onto the prey. Octopods only have four pairs of sucker-coated arms, as the name suggests, though
Japanese flying squid the squid has a siphon, a muscle which takes in water from one side, and pushes it out the other side: jet propulsion. The squid has eight arms and two tentacles with suction cups along the backs. In between the arms sits the mouth, or beak. Inside the mouth is a tooth-tongue-like appendage called the radula. Squid have ink sacs, which they use as a defense mechanism against possible predators. Squid also have three hearts. The age of a squid can be determined on the basis of its growth rings, or statoliths, when additions are appended daily to the balance