Not all animals have the same skeletal structure. Whales have bones in their "flippers" that resemble the same bones that make up the human "arm". This is called a homologous structure.
No, it doesn't. Chitin is an sort of skeleton found on the outside of such animals as insects.
enviorment
They are know as invertebrates; Sharks whose bodies are supported by cartilage, Stingrays, same deal, Slugs I don't know how their bodies are supported, and many other animals
it is animals skeleton
animals with out a skelton a worm.
No, some animals have an external skeleton like insects and crustaceans. Others have an internal skeleton like fish and birds and people. Some internal skeletons are made of cartilage like sharks and some are made of bone and cartilage together, like mammals.
Yes.
it is animals skeleton
In animals with endoskeletons, muscles surround the skeleton. In animals with exoskeletons,the skeleton surrounds the muscles.
Almost all animals have a skeleton, whether its an internal skeleton or an exoskeleton. Some animals like the Jellyfish are of without a skeleton, and they are very much ... jelly-like. Examples include earthworms, slugs, etc.
One made of bones.
The same just like with all animals with an internal skeleton: to provide structure and support to the body, as well as protection to the more vulnerable organs in the body.