What are the examples of hydro-skeleton?

- Cnidarians (Jellyfish, Hydra, Sea Anemone):

Cnidarians have a gastrovascular cavity that serves as a hydro-skeleton.

- The cavity is filled with fluid, which provides support and turgidity to the body.

- Muscles surrounding the cavity allow for movement and changes in shape.

- Platyhelminthes (Flatworms):

Flatworms, such as planarians, have a simple hydro-skeleton consisting of mesodermal tissue filled with fluid.

- The fluid-filled tissue helps maintain the flat shape and provides structural support.

- Nematodes (Roundworms):

Nematodes have a pseudocoelom, which is a fluid-filled body cavity not lined by mesodermal tissue.

- This fluid-filled cavity provides hydrostatic support and allows for body movement.

- Annelids (Segmented Worms):

Annelids, such as earthworms and leeches, have a coelom divided into compartments by septa.

- The coelomic fluid provides hydrostatic support and helps in body movement.

- Echinoderms (Starfish, Sea Urchins, Sea Cucumbers):

Echinoderms have a water vascular system consisting of fluid-filled canals and chambers.

- The water vascular system not only provides hydraulic pressure for locomotion but also functions as a hydro-skeleton, offering support and rigidity to the body.