Aschelminthes: Roundworms — NEET Biology
📚 Practice ConceptThe body of the aschelminthes is circular in cross-section, hence, the name roundworms. They may be freeliving, aquatic and terrestrial or parasitic in plants and animals. Roundworms have organ-system level of body organisation. They are bilaterally symmetrical, triploblastic and pseudocoelomate animals. Alimentary canal is complete with a well-developed muscular pharynx. An excretory tube removes body wastes from the body cavity through the excretory pore. Sexes are separate (dioecious), i.e., males and females are distinct. Often females are longer than males. Fertilisation is internal and development may be direct (the young ones resemble the adult) or indirect.
Which of the above statements are correct regarding Phylum Aschelminthes? S1: The body of Aschelminthes is circular in cross-section, which is why they are commonly called roundworms. S2: They are bilaterally symmetrical, triploblastic, and pseudocoelomate animals. S3: Their alimentary canal is complete with a well-developed muscular pharynx, and waste removal occurs through nephridia. S4: Aschelminthes exhibit sexual dimorphism, with males and females being distinct, and females are often longer than males. S5: Development in Aschelminthes is always direct, where the young ones resemble the adult.
View solution & NCERT explanation
Correct answer: B — S1, S2 and S4
Let's evaluate each statement based on the NCERT text for Phylum Aschelminthes: S1: "The body of the aschelminthes is circular in cross-section, hence, the name roundworms (Figure 4.10)." This statement is correct. S2: "They are bilaterally symmetrical, triploblastic and pseudocoelomate animals." This statement is correct. S3: "Alimentary canal is complete with a well-developed muscular pharynx. An excretory tube removes body wastes from the body cavity through the excretory pore." This statement is incorrect because waste removal occurs via an excretory tube with a pore, not nephridia. Nephridia are found in Annelids. S4: "Sexes are separate (dioecious), i.e., males and females are distinct. Often females are longer than males." This indicates sexual dimorphism. This statement is correct. S5: "Fertilisation is internal and development may be direct (the young ones resemble the adult) or indirect." This statement is incorrect because development may be direct *or indirect*, not *always* direct. Therefore, statements S1, S2, and S4 are correct.
What does NCERT say about body aschelminthes circular cross-section?
Has this concept appeared in NEET?
Which chapter is this from?
Through deep analysis of NEET and NTA, 88 of 90 questions from the NEET 2026 paper were matched straight from the MedicNEET Biology question bank.
88/90MedicNEET's Biology question bank is built from the same NCERT lines NTA picks repeatedly. Not random MCQs — questions crafted exactly like NTA crafts them.