CARBON DIOXIDE

[Elliott]

is the movement of carbon dioxide between the lungs and blood depend on diffusion gradients?
is that correct, i know diffusion but diffusion gradients any replies i wil appreciate ;

im also not sure if all blood caried away from the heart is high in oxygen concentration and low in carbon dioxide concentation
thanks
im asking for some opinions after i research in internet and my books

[canalon]

You should have researched a lot...

For the heart: what are the name of the arteries coming out of the 2 part of the heart. Where are they coming to? What is happening there? Oh my! you found your answer.

For the first one Just look at the definition of gradient. May I suggest "define:gradient" in google.