Question

Consider the following statements :
A. Annelids are true coelomates
B. Poriferans are pseudocoelomates
C. Aschelminthes are acoelomates
D. Platyhelminthes are pseudocoelomates
Choose the correct answer from the options given below :

• A. B only
• B. A only
• C. C only
• D. D only

Answer 1

The Correct Option is B

To determine the accuracy of claims about body cavity classifications within various animal phyla, it is essential to clarify the definitions of "true coelomates," "pseudocoelomates," and "acoelomates." An analysis of each claim follows:

• A. Annelids possess a true coelom: This assertion is accurate. Annelids, like earthworms, exhibit a coelom, a fluid-filled space completely enclosed by mesodermal tissue.
• B. Poriferans are pseudocoelomates: This assertion is inaccurate. Poriferans, or sponges, do not possess any true body cavity and are characterized by asymmetry and the absence of a well-defined digestive system.
• C. Aschelminthes are acoelomates: This assertion is inaccurate. Aschelminthes, also known as Nematodes, are classified as pseudocoelomates, indicating a body cavity that is not entirely bordered by mesodermal tissue.
• D. Platyhelminthes are pseudocoelomates: This assertion is inaccurate. Platyhelminthes, or flatworms, are acoelomates, meaning they lack a body cavity situated between their digestive tract and body wall.

Consequently, only statement A is correct, establishing "A only" as the appropriate selection.