Hole in one??no..it's hole in heart..

[victor]

Amphibies have three room in their hearts. They only have one ventricle so the CO2 blood is mixed with O2 blood and causing the oxygen trasportation not optimal. But this problem can be solved because amphibies have a very thin skin so oxygen can diffuse through their skin to their blood vessels.
But, how about reptiles can soleve this problem since they have thick skin and their ventricle still have one hole (even though ventricle septum is almost perfect..that's why I call it hole in heart) called Foramen Pannizae. Their blood is still mixed right? it means they'll suffer Cyano then? (blue body because oxygen transportation is not enough).

[MrMistery]

Oxygen can not diffuse through the skin of reptiles, it is too thick.
Ok, so i don't think you understand the situation very well. the main reason why amphibians need to have tegumentary respiration is that their lungs are very primitives, they have the form of bags. So they are unable to supply the body with enough oxygen. They solved the problem by tegumentary respiration. Of course, there is the fact that the blood is mixed that contributes to the small eficiency of the process. But the oxygen from the skin is brough to the heart via the cutanee vene, the oxygen doesn't simply diffuse wherever in the blood
In reptiles, lungs are much more evolved. Some of them(the most evolved ones) even have pulmonary alveola. Plus the blood does not mix so much. It is enough to keep them alive. But remember reptiles are still poikiloterms. Their respiratory system is unable to supply them with enough oxygen to assure a steady body temperature.

[victor]

So, reptiles maximize the efficiency of the blood transportation from amphibians.. Ok thanks..Oh, about poikiloterms, their oxygen are not enough, they need sunlight to increase their temperature..

[victor]

Hey..if oxygen can be brought to the heart from their skin, it means diffusion right?? is there any 'one cell formed' blood vessel near the amphibian skin?? because oxgen can only diffuse into one cell formed blood vessel...

[MrMistery]

I do not know what a one cell blood vessel is. Beneath the skin of amphibians there are capilaries. Oxygen diffuses from the air into the RBC

[Dr.Stein]

Yes, beneath the amphibians' skin there is capillary beds. And their skin is always wet/moist so the oxygene from the air can diffuse into the skin and reach capilalry beds, just like oxygene diffuse into moist alveoli and come inside plexus and capillaries within vertebrates' lung.