This enables them to squeeze through very narrow slits between underwater rocks, which is very helpful when they are fleeing from morays or other predatory fish. A beak, similar in shape to a parrot's beak, is their only hard part. They have neither a protective outer shell like the nautilus, nor any vestige of an internal shell or bones, like cuttlefish or squids. Unlike most other cephalopods, the majority of octopuses - those in the suborder most commonly known, Incirrata - have almost entirely soft bodies with no internal skeleton. These arms are a type of muscular hydrostat. Octopuses are characterized by their eight arms (not tentacles), usually bearing suction cups. if you know how many sides an octagon has then you would know how many tentacles that and octopus has. 8 dont think they have testicles the number of tentacles an octupus has is 8 because all they need is 8 tentacles to survive.
