Skeletal System
the cuticle is the closest thing Nematodes have to a skeleton. This cuticle functions as support and a leverage point for movement. The liquid in the pseudocoelem serves as a hydrostatic skeleton. The hydrostatic skeleton works when muscles contract and apply pressure to this incompressible fluid. this pressure is transmitted in every direction in the fluid. The longitudinal muscles act against the cuticle and the combination of muscle contraction, pressure on the fluid. the stretching and compressing of the cuticle gives nematodes their characteristic whip-like means of locomotion. In terms of the skeletal system, Nematoda are commonly called Roundworms and get their name from their round cross section. They have long thread-like bodies and are usually very small to microscopic, some parasitic members however can grow as big as a meter long. They have a simple tube-like gut with a mouth and an anus. They also have a perfectly cylindrical, elongated and unsegmented body structure. many roundworms are parasitic. Nematodes are thin, generally less than 2.5 millimeters (0.10 in) long. The smallest nematodes are microscopic, while free-living species can be as long as 5 centimeters (2.0 in). The body has ridges, rings, warts, bristles or other distinctive structures along itself.