You find what you believe is a new species of animal. Which of the following characteristics would enable you to argue that it is more closely related to a flatworm than it is to a roundworm?

Question

Quizplus · Accepted Answer

Both flatworms and roundworms belong to the phylum Nematoda, which is characterized by having a cylindrical body, a cuticle that is not shed, and a pseudocoelom (a body cavity not completely lined with mesoderm). Flatworms, on the other hand, belong to the phylum Platyhelminthes, which is characterized by having a flattened body, a cuticle that is shed to grow, and no coelom. Therefore, the absence of a coelom would be the characteristic that would enable you to argue that the new species is more closely related to a flatworm than to a roundworm.

You Find What You Believe Is a New Species of Animal