Question

Which of the following is a structure unique to parasitic worms such as tapeworms?

1) Nephridia
2) Flame cells
3) Scolex
4) Malpighian tubules

Answer 1

The scolex is the unique structure found in parasitic worms such as tapeworms, utilized for attachment to the host's intestinal wall. Nephridia and flame cells are excretory structures in earthworms and flatworms, and Malpighian tubules serve a similar excretory role in insects.

So, the correct answer is 3) Scolex.

Step-by-step explanation:

The structure unique to parasitic worms such as tapeworms is the scolex. Unlike nephridia, which are found in earthworms, and flame cells, which are found in planaria and other flatworms including parasitic tapeworms, the scolex is specifically adapted for attachment within the host's digestive system. The scolex is equipped with hooks, which allow the tapeworm to attach to the intestinal wall of its host.

This is distinct from the functions of nephridia and flame cells, which are primarily involved in excretion and osmoregulation, and Malpighian tubules which serve a similar role in insects.

So, the correct answer is 3) Scolex.