Pls........?

Question

Why is it necessary to separate oxygenated and deoxygenated blood in mammals and birds?

Answer 1

Deoxygenated blood is the blood which is used by organs of the body. So, in order to prevent the re-circulation of this same blood, there are blood capillaries which help in preventing mixing up of deoxygenated and oxygenated blood !!! So, it is not only necessary to separate oxygenated and deoxygenated blood in mammals and birds, but also in other organisms where blood is present! Hope that helped!!!!!

Answer 2

It is necessary to separate oxygenated and deoxygenated blood in animals to efficiently process the blood for further use.  If the blood goiing to a muscle had 50% of the oxygen it should have twice as much would be needed for respiration and cell metabolic functions.  

This would also imply the blood would have waste products floating around in it as well.  This could cause a harmful buildup in the cells.