There are three main types of arteries:
- Elastic arteries.
- Muscular arteries.
Arteries have a great deal more smooth muscle within their walls than veins, thus their greater wall thickness. This is because they have to carry pumped blood away from the heart to all the organs and tissues that need the oxygenated blood.
All arteries and veins contain three layers. The innermost layer is called the tunica intima. The muscular middle layer is called the tunica media, and the outermost layer is called the tunica adventitia. Because capillaries are only one cell layer thick, they only have a tunica intima.
Arteries carry oxygenated blood away from the heart to the tissues, except for pulmonary arteries, which carry blood to the lungs for oxygenation (usually veins carry deoxygenated blood to the heart but the pulmonary veins carry oxygenated blood as well).
Veins can be categorized into four main types: pulmonary, systemic, superficial, and deep veins.
- Pulmonary veins carry oxygenated blood from the lungs to the left atrium of the heart.
- Systemic veins return oxygen-depleted blood from the rest of the body to the right atrium of the heart.
The chief difference between arteries and veins is the job that they do. Arteries carry oxygenated blood away from the heart to the body, and veins carry oxygen-poor blood back from the body to the heart. Your body also contains other, smaller blood vessels.
An artery is a vessel that carries blood away from the heart and toward other tissues and organs. Arteries are part of the circulatory system, which delivers oxygen and nutrients to every cell of the body.
The Coronary Arteries are the blood vessels that supply blood to your heart. They branch off of the aorta at its base. The right coronary artery, the left main coronary, the left anterior descending, and the left circumflex artery, are the four major coronary arteries.
The largest artery is the aorta, the main high-pressure pipeline connected to the heart's left ventricle. The aorta branches into a network of smaller arteries that extend throughout the body. The arteries' smaller branches are called arterioles and capillaries.
This is a list of arteries of the human body.
- The aorta.
- The arteries of the head and neck. The common carotid artery. Relations.
- The arteries of the upper extremity. The subclavian artery. The axilla.
- The arteries of the trunk. The descending aorta. The thoracic aorta.
- The arteries of the lower extremity. The femoral artery.
A distributing artery (or muscular artery) is a medium-sized artery that draws blood from an elastic artery and branch into "resistance vessels" including small arteries and arterioles. Under the microscope distributing arteries can be identified by their clearly defined internal elastic lamina.
Heart & Blood Vessels: Your Coronary Arteries. The heart receives its own supply of blood from the coronary arteries. Two major coronary arteries branch off from the aorta near the point where the aorta and the left ventricle meet. These arteries and their branches supply all parts of the heart muscle with blood.
The wall of an artery consists of three layers. The innermost layer, the tunica intima (also called tunica interna), is simple squamous epithelium surrounded by a connective tissue basement membrane with elastic fibers. The middle layer, the tunica media, is primarily smooth muscle and is usually the thickest layer.
Vasodilation is the widening of blood vessels. It results from relaxation of smooth muscle cells within the vessel walls, in particular in the large veins (called venodilators), large arteries, and smaller arterioles. The process is the opposite of vasoconstriction, which is the narrowing of blood vessels.
Examples of elastic arteries include the aorta, pulmonary trunk, and brachiocephalic trunk. Muscular arteries (distributing arteries) are medium-sized arteries. The elastin in muscular arteries is confined to two circumscribed rings: the internal elastic lamina and the external elastic lamina.
Veins have the same three layers as arteries and are elastic, but they have a less-muscular middle layer, making their walls thinner. Also, unlike arteries, some veins have valves (tissue flaps) that permit blood to flow in only one direction, back to the heart.
The arteries (red) carry oxygen and nutrients away from your heart, to your body's tissues. The veins (blue) take oxygen-poor blood back to the heart. Arteries begin with the aorta, the large artery leaving the heart.
Blood vessels are found throughout the body. There are five main types of blood vessels: arteries, arterioles, capillaries, venules and veins. Arteries carry blood away from the heart to other organs. They have very thin walls which allow nutrients from the blood to pass into the body tissues.
Elastic arteries include the largest arteries in the body, those closest to the heart, and give rise to the smaller muscular arteries. The pulmonary arteries, the aorta, and its branches together comprise the body's system of elastic arteries.
It pumps blood out at high pressure so that it can reach all the parts of the body quickly. To withstand the pressure of the blood coming out from the heart, arteries need thick walls. The returning blood in the veins is under low(er) pressure. Because of the lower pressure, vein walls are thinner.
The arteries are perceived as carrying oxygenated blood to the tissues, while veins carry deoxygenated blood back to the heart. This is true of the systemic circulation, by far the larger of the two circuits of blood in the body, which transports oxygen from the heart to the tissues of the body.