NEET BIOLOGY

Detailed explanation-1: -Aschelminthes are commonly known as roundworms. They are characterized by the presence of a pseudocoelom. It is now an obsolete phylum of invertebrates and the animals grouped under this are now kept in ten different phyla.

Detailed explanation-2: -Solution : In Aschelminthes, the body cavity is not lined by mesoderm, instead, the mesoderm is present as scattered pouches in between the ectoderm and endoderm. Hence, they are called pseudocoelomates.

Detailed explanation-3: -Identifying Characters of Aschelminthes: Pseudocoelom: They have pseudocoelom in the body. There is no mesoderm in the body cavity. Muscular system: Advanced types of the muscular system and consists of longitudinal and round muscle tissues. Body membrane: Body covered with a layered cuticle.

Detailed explanation-4: -Pseudocoelomate metazoans have a fluid-filled body cavity, the pseudocoelom, which, unlike a true coelom, does not have a cellular peritoneal lining. Most of the pseudocoelomates (e.g., the classes Nematoda and Rotifera) are small and none possess an independent vascular system.

Detailed explanation-5: -Aschelminths used to be referred to as “pseudocoelomates”–an alternative name for the taxon is Pseudocoelomata–because of their supposed shared internal structure.