NEET Biology: Animal Physiology questions with solutions

Q1. Assertion Double circulation is incomplete in amphibians and reptiles Reason Unlike in birds and mammals, in amphibian and reptiles, the left atrium receives oxygenated blood and right atrium receives deoxygenated blood.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Answer: Assertion is correct but Reason is incorrect

The assertion is correct because amphibians and most reptiles do not have complete separation of oxygenated and deoxygenated blood, so double circulation is incomplete. The reason is incorrect because the atrial blood pattern described is not the distinguishing issue here, and it does not accurately explain the incompleteness.