Class 11 NEET Biology Structural Organisation in Animals

(c) : Hydraulic skeleton is the system of support found in soft bodied invertebrates, which relies on the incompressibility of fluids contained within the body cavity. In earthworms the coelomic fluid is under pressure within the coelom and therefore provides support for internal organs. Due to hydraulic skeleton, during burrowing, the anterior end becomes turgid and aids in relaxation of longitudinal muscles.