NEETZoologyBreathing and Exchange of Gases
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): Lower invertebrates like sponges, coelenterates, and flatworms exchange O₂ with CO₂ by simple diffusion over their entire body surface. Reason (R): Mechanisms of breathing vary among different groups of animals depending mainly on their habitats, but are independent of their levels of organisation.
Options
- ABoth (A) and (R) are correct and (R) is the correct explanation of (A)
- BBoth (A) and (R) are correct but (R) is not the correct explanation of (A)
- C(A) is correct but (R) is not correct
- D(A) is not correct but (R) is correct
Correct answer
C. (A) is correct but (R) is not correct
Step-by-step solution
Assertion (A) is correct because lower invertebrates such as sponges, coelenterates, and flatworms lack complex respiratory organs and rely on simple diffusion over their entire body surface for the exchange of gases. Reason (R) is incorrect because the mechanisms of breathing vary among different groups of animals depending mainly on both their habitats and their levels of organisation, not independent of the latter. Answer: (A) is correct but (R) is not correct