Question

Parasitic nematodes, much like their free-living counterparts, are widely distributed and well adapted for their mode of existence. Discuss in detail the adaptations of these parasitic nematodes and compare their adaptations to those of trematodes and cestodes with respect to their ability to survive in the gut of the definitive host, arguably a very harsh environment. (long answer)

Answer 1

Parasitic nematodes are nematodes that are parasitic to plants and insects. They are round-shaped and small-sized worms. As they are parasitic in nature, they derive all the nutrients for their growth and survival from the plant and insect. In this process, it can also cause the death of the host. The parasitic nematodes over the period of time have undergone a series of adaptations to fulfil the changes in environmental factors. Trematodes and Cestodes are flatworms and tapeworms respectively. They are also parasitic in nature. Both of them have a complex life cycle and thus their dependence on at least 2 hosts for completion of their life cycle was a part of their adaptation. The adaptations made my trematodes and cestodes include sucker and hooks which aid them in the process of attachment. On the other hand, one critical adaptive feature of the parasitic nematode was the presence of a cuticle which was permeable to liquid and gases but was still very sturdy and hard. This characteristic made the process of respiration easier.