Main Classes of Blood Vessels – Blood vessels and blood circulation

00:01 Welcome back to the second basic lecture in vascular medicine.

00:05 During this lecture, we’re going to go into a little more detail concerning the blood vessels and how they function in the circulation.

00:15 You’ll remember from the last lecture that we talked about the main classes of blood vessels. That’s what we’re going to talk about first: the artery system and the venous system and the capillaries.

00:29 So here’s a little diagram that shows you. We’ve seen this one before actually. It shows you that the arteries start out large and progressively become smaller eventually ending in arterioles that are the major resistance factor in the circulation. Then we arrive at the capillaries where most of the nutrient and waste exchange goes on with the cells of the body. And then that blood collects in small venules, eventually large veins and returns to the heart.