Question

The three chambered heart of frog is not as efficient as the four chambered human heart because

• A. oxygenated and deoxygenated blood gets mixed up
• B. ventricle does not pump blood properly
• C. it does not hold enough blood
• D. the heart muscles are not strong

Answer 1

The correct option is A oxygenated and deoxygenated blood gets mixed up

Three chambered hearts are seen in all amphibians and most reptiles. There are two atria and one ventricle. There are separate blood vessels that carry oxygenated blood to the body and vessels that bring the deoxygenated blood to the right atrium. Both the atria empty into a single ventricle due to which the blood gets mixed up.
In a four chambered heart like in humans, the deoxygenated blood and oxygenated blood remains in separate compartments and hence, it is not mixed. So, the oxygenated blood pumped by four chambered heart has more oxygen content than the three chambered heart.
Hence, the three chambered heart is not as efficient as the four chambered heart.