Question

Give the correct hierarchical classification of roundworms.
a. Kingdom- Animalia
     Phylum- Annelida
b. Kingdom- Animalia
     Phylum- Platyhelminthes
c. Kingdom- Animalia
     Phylum- Nematoda
d. Kingdom- Animalia
     Phylum- Arthropoda

Answer 1

Hint: The scientific name of roundworms is Ascaris lumbricoides which is a nematode. It is a parasite which occurs in the small intestine of humans and causes a disease called ascariasis. Since it is an animal it belongs to the highest category called kingdom Animalia.

Complete answer:
- Roundworm or Ascaris lumbricoides belong to the phylum Nematoda or Aschelminthes or Nemathelminthes of kingdom Animalia.
- Ascaris belongs to class Chromadorea, order Ascaridida, family Ascarididae.

The scientific classification of Ascaris lumbricoides is:
Kingdom- Animalia
Phylum- Nematoda
Class- Chromadorea
Order- Ascaridida
Family- Ascarididae
Genus- Ascaris
Species- lumbricoides

- The body of Ascaris is round in shape, hence the name roundworms.
- It is unisexual i.e. sexes are separate from well-marked sexual dimorphism.
- Diseases caused by Ascaris are known as ascariasis and it is treated with oil of chenopodium which has anthelmintic properties.
- The body length of the female Ascaris is larger than that of male Ascaris.
- Its body cavity is called pseudocoelom or false coelom, derived from embryonic blastocoel.
- It is an endoparasite found in the small intestine of humans with worldwide distribution.

Hence, the correct answer is option (C).

Note: The taxonomic hierarchy was first used by Linnaeus and it is the arrangement of taxonomic categories in descending order from higher to lower in biological classification. Roundworms are kept in phylum Nematoda as it includes true worms or threadworms. Thus roundworms have characters similar to this phylum.