An exoskeleton - i.e. a shell.
A crayfish is not a fish because they have bones on the outside of their body fish don't.
Animals with bones on the outside have an exo-skeleton. Crabs, crayfish, lobsters and many insects have their bones on the outside.
Nope. They have a shell, known as an exoskeleton. Means bones are on the outside (the shell takes the place of bones)
Exoskeleton: Crayfish have a hard shell, and no bones. That makes crayfish invertebrates (no spine). Gills: Crayfish respire underwater through gills, where humans use lungs. The circulatory system is the second one, the reason for this being that crayfish have no blood vessels (and humans obviously do).
A crayfish has gills, which are specialized organs used for breathing underwater. They extract oxygen from the water as it flows over them. Crayfish do not have feathers or scales; instead, their bodies are covered with a hard exoskeleton.
I am not sure, but from what I can conclude from diagrams and from a recent dissection no, the crayfish does not have a liver. Although you should consider asking your biology teacher just to be sure.
A crayfish can have as many eggs as it wants it just has to be healthy but I think it can lay 50-200.
No, tarantulas do not have bones. They, like all arthropods, have an exoskeleton instead.
Yes
Crayfish
Crayfish can hear, but they do not have ears, so they do not hear in the usual sense. Our ears pick up vibrations via the eardrum and tiny bones in our ears, but crayfish have thousands of sensory bristles. Some of these sensory bristles respond to chemicals, others to touch, but either way, they enable te crayfish to not only hear, but also to smell and feel.
Butterflies do not have bones. Instead, they have an exoskeleton made of chitin. This exoskeleton provides support and protection for their bodies.