How the Cardiovascular System Works – Introduction to the Cardiovascular System

00:00 Finally, let's talk about the final learning objective. How does the cardiovascular system work? Well here we see a diagram that shows you in picture form all the functions of a cardiovascular system. We have already mentioned them as we have gone along here. Of course essential to the entire system is the heart pumping the blood. The arteries, seen on the left with a red line in the channel, transport the red blood which is full of oxygen away from the heart. As we have said, the arteries divide eventually arriving in the arterioles, the resistance factor in the cardiovascular system and from there into the capillaries.

00:43 Notice how thin walled they are. So that only one red blood cell at a time can get through.

00:49 This small size allows the red blood cells to release their oxygen, to pick up carbon dioxide, waste product from the cells, and then to pass into the little tiny veins, the venules and then into larger veins, you can see on the right hand side of the diagram, the blue arrow, showing the veins carrying the blood back to the right side of the heart, where it will be transported into the lungs to give off carbon dioxide, take on oxygen, and then eventually make their way back to the left side of the heart as red blood to be pumped out to the body again in a never ending circle.