Mollusks are creatures that protect themselves in a shell type thing to help protect themselves. These creatures are invertebrates because they have no backbones and also because they don't have any bones inside their body. For the average snail, the shell is considered a bone because it is as strong as a bone. Mollusks can either live on land or underwater depending on where natural selection was better for them. Mollusks shells seem to be similar to the human bones because it gives the creature support and protection from others, while these bones only give humans support. They are bilaterally symmetrical.
Examples: Snails, Squids, Octupuses
Examples: Snails, Squids, Octupuses