500
Name the 3 blood vessels that the heart pumps blood through and tell what they do-be specific.
What are the arteries-carry blood away from the heart (most carry oxygen rich blood, pulse in wrist is artery, thick walls).
capillaries-branching from the smallest arteries, they are the smallest blood vessels in the body, oxygen and dissolved nutrients diffuse through capillary walls at same time, wastes diffuse into the blood. Capillaries narrow when cold to keep heat in, and expand when warm to let heat out.
veins-connect arteries to veins, thin walled blood vessels, carry blood to the heart.