Could you explain a bit about the structural differences between arteries, arterioles, veins and capillaries?
What sorts of cells are important to the functions of each type of blood vessle?
How doe these blood vessels differ from each other in their specialized functions?
Where might we find each of these types of blood vessel?
Also I was wondering if you could give us an idea about what types of stuff comprises blood?
Aside from the nutrients and wastes it transports, what does blood contain? What sorts of cells might we expect to find there?