Question

Which one of the following is not a characteristic of Annelida?

• A. Metanephridia
• B. Segmentation
• C. Pseudocoelom
• D. Clitellum

Answer 1

The correct option is C Pseudocoelom

Annelids are coelomate animals which means that they possess a true coelom. The pseudocoelom is a fluid-filled body cavity lying inside the external body wall of the nematode.They have long thin bodies composed of a series of identical segments. These segments lie between the head, comprised of a prostomium, a mouth and sometimes a peristomium, and a tail called a pygidium. A clitellum is part of the reproductive system of an annelid. The clitellum is a thick, saddle-like, ring found in the epidermis (skin) of the worm. The nitrogenous waste products of metabolism diffuse from the body's cells into the fluid of the coelom. The coelomic fluid is slowly drained into small tubular organs, called metanephridia. As the fluid passes through the metanephridia it can exchange some materials with the network of blood vessels that are intertwined around the tubule.