Question

Which of the following animals has a true coelom?

• A. Ascaris
• B. Pheretima
• C. Sycon
• D. Taenia solium

Answer 1

Answer: (B)

The true coelom is a body cavity which arises as a cavity in embryonic mesoderm. In this case, the mesoderm of the embryo provides a cellular lining, called coelomic epithelium or peritoneum, to the cavity. The coelom is filled with coelomic fluid secreted by the peritoneum. The animals which have true coelom are called eucoelomates or coelomates, eg, annelids, echinoderms and chordates. Among given option Pheretima (annelid) has tme coelom (shizocoel). The coelom is filled with milky white alkaline coelomic fluid.