Artery - definition and function

Artery - definition and function - picture » The cardiovascular system » Artery definition and function

Artery is a flexible, muscular BLOOD vessel that carries blood from the HEART and oxygenated blood to tissues throughout the body. The wall of an artery has three layers:

  • adventitia, the outermost layer, which is primarily connective tissue that gives the artery its FLEXIBILITY
  • media, the middle layer, which is mostly smooth MUSCLE tissue that gives the artery the ability to contract and relax
  • intima, the inner layer, which is epithelial tissue that provides a smooth surface to facilitate the flow of blood

The adventitia is more prominent in larger arteries such as the AORTA and the carotid arteries, encasing the artery in a weblike fashion without clear direction to its fibers. In smaller arteries, the media often dominates the artery’s structure. The muscle fibers of the media encircle the artery, helping strengthen and stabilize the artery’s walls. The delicate intima contains two structural levels, the basement or foundation membrane and the subepithelial layer, both of which run lengthwise. Each may be only a cell’s thickness in small arteries, indistinguishable without magnification.

The intima’s two-level structure gives the artery its ability to carry blood cells without having them stick to its inner walls. However, it also makes the artery vulnerable to ATHEROSCLEROSIS, which develops between the intima’s two levels. The tiniest of the body’s arteries, about the thickness of a hair, are arterioles. The body’s largest artery is the aorta, which carries blood from the heart to the network of arteries that then carry the blood throughout the body.

Fibrous sheaths enclose most of the body’s arteries, usually along with the companion VEIN and NERVE. These sheaths often parallel skeletal structures for protection and stability, or run deep within the body. Arteries also receive blood themselves from other arteries, which deliver oxygen and other nutrients to the layers of the artery, and contain nerves that deliver the signals to constrict or dilate. The walls of the arteries constrict and dilate in wavelike contractions that coordinate with the heartbeat to help push blood through the body. These pulsations are detectable as the PULSE at points where the artery is near the surface of the skin, such as at the wrist and the groin.

For further discussion of the artery within the context of cardiovascular structure and function, please see the overview section “The Cardiovascular System.”


Resource: Facts On File Encyclopedia Of Health And Medicine

Each atricle being rated on a scale of 1 to 5 stars.
Please rate this article
Article Rating: 2,4 stars of 5

Discussion and opinions:

Insert your opinion:

Tweet this page

Other Articles

Aerobic fitness and Cardiovascular System

The cardiovascular system |

Aerobic Fitness and Cardiovascular System The efficiency with which the cardiovascular system functions to meet the oxygen needs of cells throughout the body, particularly under the increased pressure of intense physical activity or exercise. The higher a person’s aerobic FITNESS LEVEL, the more air the LUNGS can take in each breath, the more oxygen

Aging, cardiovascular changes that occur with

The cardiovascular system |

The most significant age-related changes in cardiovascular function occur at birth in both sexes and with MENOPAUSE in women. Though changes in METABOLISM occur with aging that affect all body systems, researchers now believe cardiovascular health does not inherently decline simply as a function of aging. DIABETES, OBESITY, lack of physical exercise, and

Aneurysm definition and symptoms

The cardiovascular system |

What is Aneurysm and Definition Aneurysm is a weakened and often distended (stretched) area in the wall of an ARTERY. Though an aneurysm may develop in any artery, the most common location is the descending or abdominal AORTA. An aneurysm is potentially life-threatening. The continual pressure of the BLOOD flowing through the artery pressures the weakened

Wolff-Parkinson-White syndrome

The cardiovascular system |

What is Wolff-Parkinson-White syndrome Wolff-Parkinson-White syndrome - An inherited ARRHYTHMIA disorder in which an extra conduction pathway, called an accessory pathway, exists between the heart’s atria and ventricles. The accessory pathway allows the heart’s electrical pacing impulse to bypass the normal conductive route, reaching the

Ventricular fibrillation - treatment

The cardiovascular system |

What is Ventricular Fibrillation Ventricular fibrillation - Rapid, irregular, ineffective contractions of the heart’s ventricles. Ventricular fibrillation quickly becomes fatal without treatment. The HEART cannot pump blood to the LUNGS or to the body when it is in ventricular fibrillation. Ventricular fibrillation is a life-threatening event that

Ventricular assist devices (VADs)

The cardiovascular system |

What is Ventricular assist devices (VADs) Ventricular Assist Devices - Implanted mechanical pumps that aid the native HEART, taking over some of the workload of the ventricles. Several types of VADs are available, each with somewhat different features and functions. A VAD may assist the right or left ventricle, and in some cases both ventricles, as a

Venogram - diagnostic procedure - definition

The cardiovascular system |

What is Venogram - diagnostic procedure Venogram is a diagnostic procedure to evaluate the flow of blood in the veins, usually in the legs. The cardiologist may use venogram to diagnose VARICOSE VEINS, VENOUS INSUFFICIENCY, or DEEP VEIN THROMBOSIS (DVT). For venogram, the radiologist injects a small amount of contrast dye into the affected VEIN network and

Chronic Venous Insufficiency - symptoms and treatment

The cardiovascular system |

What is chronic Venous Insufficiency and Symptoms Venous insufficiency is a chronic condition in which the veins cannot adequately return BLOOD to the HEART, usually as a consequence of defective valves that allow blood to leak back and pool in the veins. Some people do not have valves in their veins, a circumstance that is a CONGENITAL ANOMALY. Venous

Vena Cava - Function and definition

The cardiovascular system |

Vena Cava are the two largest veins in human body together called the venae. These veins collectively return deoxygenated BLOOD to the HEART. Both of them deplete all the blood into the right atrium. The superior vena cava, large but short vein, brings blood from the upper part of the organism, the head and upper limbs, and empties into the top of the right

Vein - what is and definition

The cardiovascular system |

What is Vein and Definition Vein - A blood vessel that carries BLOOD to the HEART. All veins except the PULMONARY VEINS carry deoxygenated blood; the pulmonary veins return oxygenated blood to the heart from the LUNGS. Because veins lack the muscular structure and contractile capability of arteries, they have valves that keep blood moving only in one