AP BIOLOGY

Detailed explanation-1: -Invertebrates without skeletons include centipedes, millipedes, worms, jellyfish, octopuses and squids. Because these animals have no hard bones, they are extremely flexible.

Detailed explanation-2: -Jellyfish are the free-swimming marine members of the phylum cnidaria. They inhabit marine waters. They do not have eyes, brains, or skeletons.

Detailed explanation-3: -Hydrostatic skeleton: Skeletal support provided by hydrostatic pressure from a fluid filled cavity (e.g. the coelum) surrounded by muscles. Hydrostatic pressure provides skeletal support in sea anemones, jellyfish, nematodes, annelids, echinoderms, and other groups.

Detailed explanation-4: -Slugs, leeches, and jellyfish have soft bodies and no exoskeleton. The pressure of fluids inside their bodies maintains their shape. Like most invertebrates, sea urchins have relatively complex internal organs.

Detailed explanation-5: -Earthworms are invertebrates, which means they do not have a backbone. In fact, they don’t have any kind of bones, legs, eyes, or teeth.