Structure of blood vessel

Structure of blood vessel

1. STRUCTURE OF BLOOD VESSEL

2. These are the part of the circulatory system, and microcirculation, that transports blood throughout the human body. OR Is a tubular structure carrying blood through the tissues and organs; a vein, artery, or capillary BLOOD VESSELS

3. There are three major types of blood vessels Arteries W hich carry the blood away from the heart It carries oxygenated blood except pulmonary TYPES OF BLOOD VESSELS

4. Veins Which carry blood from the capillaries back toward the heart. It carries deoxygenated blood except pulmonary vein CONTINUE…

5. Capillaries Which enable the actual exchange of water and chemicals between the blood and the tissues CONTINUE…

6. The arteries and veins have three layers Tunica intima Tunica media (thicker in arteries) Tunica externa /Adventitia (thicker in veins) STRUCTURE OF VEINS & ARTELIES

7. Tunica intima is the thinnest layer in both vein and arteries It is a single layer of simple squamous endothelial cells glued by a polysaccharide intercellular matrix It is surrounded by a thin layer of subendothelial connective tissue TUNICA INTIMA

8. It is interlaced with a number of circularly arranged elastic bands called the internal elastic lamina. CONTINUE…

9. Tunica media is the thickest layer in arteries It is circularly arranged elastic fiber, connective tissue, polysaccharide substances, T he second and third layer are separated by another thick elastic band called external elastic lamina. TUNICA MEDIA

10. The tunica media may (especially in arteries) be rich in vascular smooth muscle, which controls the caliber of the vessel. Veins don't have the external elastic lamina, but only an internal one. This layer is thicker in the arteries than it is in the veins CONTINUE…

11. Tunica adventitia is the thickest layer in veins It is entirely made of connective tissue It also contains nerves that supply the vessel as well as nutrient capillaries (vasa vasorum ) in the larger blood vessels This layer is thicker in the veins than it is in the arteries TUNICA ADVENTITIA

12. Capillaries consist of little more than a layer of endothelium and occasional connective tissue. STRUCTURE OF CAPILLARIES

13. This is the region where blood vessels connect and diffusion of vascular supply takes place. Anastomoses provide critical alternative routes for blood to flow in case of blockages. ANASTOMOSIS

14. NOTE: A few structures such as cartilage and the lens of the eye do not contain blood vessels. There is a layer of muscle surrounding the arteries and the veins which help contract and expand the vessels. This creates enough pressure for blood to be pumped around the body. Blood vessels are part of the circulatory system, together with the heart and the blood . CONTINUE…