Differentiate between arteries, veins and capillaries.
Why blood capillaries are important for both arteries and veins?
Collect oxygenated blood from artery and return de-oxygenated blood to vein
Collect de-oxygenated blood from artery and return oxygenated blood to vein
Collect pathogens from veins and release into artery
Collect white blood cells from artery and pour it into vein