Question

In mammals and birds why is it necessary to separate oxygenated and deoxygenated blood?

Answer 1

Warm-blooded animals such as birds and mammals maintain constant body temperature by cooling themselves when they are in a hotter environment and by warming their bodies when they are in a cooler environment. Hence, these animals require more oxygen for more cellular respiration so that they can produce more energy to maintain their body temperature.

Thus, it is necessary for them to separate oxygenated and deoxygenated blood, so that their circulatory system is more efficient and can maintain their constant body temperature.