Answer to Question #178553 in Zoology for Ali

Question

Campare and contrast the hydraulic skeleton of molluscs with hydrostatic skeleton of cnidarian and pseudocoelomates

Answer 1

1. in both the fluid contained within them is subjected to compression by the body walls. This compression helps the organism to move from one place to another; thus they help in locomotion.
2. In hydraulic skeleton blood is confined within tissue spaces. the body muscles, which are attached to the body wall compress the blood present between the tissue spaces and this compression causes body parts to be moved while in hydrostatic water is the primary fluid in the case of cnidarians contractile cells line the gastrovascular cavity that contract and push water forward helping in movement.
3. in pseudocoelomates mesenchyme cells present in the fluid gelatinous pseudocoelom acts as the hydrostatic skeleton.