EVERYDAY SCIENCE

Detailed explanation-1: -It’s found in creatures from the phylum Aschelminthes and Nematoda.

Detailed explanation-2: -The pseudocoelomates belong to the phylum Nematoda/Aschelminthes. Mesoderm is a layer of cells that lines the organism’s bodily cavity. A coelom is the name for this bodily cavity.

Detailed explanation-3: -Acoelomate: Flatworms don’t have any kind of coelom or pseudocoelom; their bodies are basically solid. This simple body structure led biologists to conclude that the phylum Platyhelminthes branched off from the rest of the animals before the evolution of the coelom.

Detailed explanation-4: -Nematodes are called “pseudocoelomates” because in most forms, their coelom is not completely lined with mesodermally derived cells and they are triploblastic. Possessing no circular body muscles, movement is accomplished by contraction and relaxation of longitudinal muscles in apposition to a hydrostatic skeleton.

Detailed explanation-5: -But the animals belonging to phylum Annelida that have true or well-developed coelom are called coelomates. Thus being ‘pseudocoelomate’ is the only character not possessed by animals of the phylum Annelida.