Power Point P4

Circulatory System Cardiologist: Dr. Christine, Dr. Juan & Dr. Julisa

Function of the Circulatory System The circulatory system is a group of organs that transport blood and the substances it carries to and from all parts of the body. The circulatory system can be considered as composed of two parts: the systemic circulation, which serves the body as a whole except for the lungs, and the pulmonary circulation, which carries the blood to and from the lungs. The organs of circulatory system consist of vessels that carry the blood and a muscular pump, the heart, that drives the

Blood flow in the Heart.

Organs Involved • The main components of the human circulatory system are the heart, the blood, and the blood vessels. The circulatory system includes: the pulmonary circulation, a "loop" through the lungs where blood is oxygenated; and the systemic circulation, a "loop" through the rest of the body to provide oxygenated blood. An average adult contains five to six quarts (roughly 4.7 to 5.7 liters) of blood, which consists of plasma, red blood cells, white blood cells, and platelets. Also, the digestive system works with the circulatory system to provide the nutrients the system needs to keep the heart pumping.

Heart

• The heart pumps oxygenated blood to the body and deoxygenated blood to the lungs. In the human heart there is one atrium and one ventricle for each circulation, and with both a systemic and a pulmonary circulation there are four chambers in total: left atrium, left ventricle, right atrium and right ventricle. The right Atrium, which is the upper chamber of the right side. The blood that is returned to the right atrium is deoxygenated (poor in oxygen) and passed into the right ventricle to be pumped through the pulmonary artery to the lungs for re-oxygenation and removal of carbon dioxide. The left atrium receives newly oxygenated blood from the lungs as well as the pulmonary vein which is passed into the strong left ventricle to be pumped through the aorta to the tissues of the body

Pulmonary & Systemic circulation • Pulmonary circulation is the portion of the cardiovascular system which transports oxygen-depleted blood away from the heart, to the lungs, and returns oxygenated blood back to the heart. • Systemic circulation is the portion of the cardiovascular system which transports oxygenated blood away from the heart, to the rest of the body, and returns oxygendepleted blood back to the heart. Systemic circulation is, distance-wise, much longer than pulmonary circulation, transporting blood to every part of the body except the lungs.

The circulatory system transports materials throughout the body.

The Circulatory system includes three types of blood vessels- arteries, veins, and capillaries- that act as a transportation network for the blood. • Arteries are strong and flexible. They must carry blood away from the heart under great pressure. Their thick muscle layer and elastic fibers allow the artery to expand & contract to help move the blood. Smaller arteries, called arterioles, connect arteries capillaries. • Veins carry blood under much less pressure back to the heart. They have a larger diameter and thinner walls than do arteries and contain valves that prevent blood from flowing backwards. Veins need the pressure of skeletal muscles pushing against their walls to keep blood moving. Smaller veins, called venules, connect larger veins to capillaries. • Capillaries have thin walls, only once cell thick, that allow materials to diffuse into and out of the blood. In some organs such as the liver or kidneys, capillary beds move a large volume of blood into and out of the organs.

Health Unhealthy lifestyle choices can increase the risk of developing circulatory diseases. The artery walls may becomes thick and inflexible or may be blocked by sticky plaque, leading to a possible heart attack or stroke. Treatments include balloon angioplasty or bypass surgery. Healthy lifestyle choices and some medications can greatly reduce the risk of heart disease.