When reptiles stop breathing, for example on extended dives,
A) blood is shunted from the systemic circuit to the pulmonary circuit.
B) blood is shunted specifically to the brain.
C) blood is shunted from the pulmonary circuit to the systemic circuit.
D) blood is shunted to the skin for gas exchange.
E) the pattern does not change between the breathing and the nonbreathing periods.

Question

Quizplus · Accepted Answer

When reptiles stop breathing, blood is shunted from the pulmonary circuit (lungs) to the systemic circuit (rest of the body). This is because reptiles have a three-chambered heart and cannot completely separate oxygenated (from lungs) and deoxygenated (from tissues) blood. Therefore, the shunting of blood helps to maintain oxygen supply to the vital organs during extended dives.

When Reptiles Stop Breathing, for Example on Extended Dives