Psuedocoelomate ?

Before have a idea about coelom! In some protostomes, the embryonic blastocoele persists as a body cavity. These protostomes have a fluid filled main body cavity unlined or partially lined with tissue derived from mesoderm. This fluid-filled space surrounding the internal organs serves several functions like distribution of nutrients and removal of waste or supporting the body as a hydrostatic skeleton. A pseudocoelomate or blastocoelomate is any invertebrate animal with a three-layered body and a pseudocoel. The coelom was apparently lost or reduced as a result of mutations in certain types of genes that affected early development. Thus, pseudocoelomates evolved from coelomates.[14] "Pseudocoelomate" is no longer considered a valid taxonomic group, since it is not monophyletic. However, it is still used as a descriptive term. Important characteristics: lack a vascular blood system diffusion and osmosis circulate nutrients and waste products throughout the body. lack a skeleton hydrostatic pressure gives the body a supportive framework that acts as a skeleton. no segmentation body wall epidermis and muscle often syncytial usually covered by a secreted cuticle most are microscopic parasites of almost every form of life (although some are free living) eutely in some loss of larval stage in some possibly pedomorphism

Invertebrate organisms whose body cavity is not derived from a MESODERM, as in coelomates, and thus, have pseudocoels are called PSEUDOCOELOMATES. Eg :- roundworms.