Blood circulation

this ppt is related with circulatery system of humans. this also relates blood vessels, heart diseases,and many facts related to body parts...

1. B lood, H eart and C irculation

2. The  circulatory system , also called the cardiovascular system  or the vascular system, is an organ system that permits blood to circulate and transport nutrients (such as amino acids and electrolytes), oxygen, carbon dioxide, hormones, and blood cells to and from the cells in the body to provide nourishment and help in fighting diseases, stabilize temperature and pH, and maintain homeostasis. The study of the blood flow is called  hemodynamics . The study of the properties of the blood flow is called  hemorheology .

3. The essential components of the human cardiovascular system are the heart, blood and blood vessels. It 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, accounting for approximately 7% of their total body weight.  

4. Relative percentages of cardiac output delivered to major organ systems

5. Arteries  are blood vessels that carry blood away from the heart.. The effective arterial blood volume is that extracellular fluid which fills the arterial system. Arteries form part of the circulatory system. They carry blood that is oxygenated after it has been pumped from the heart. Arteries also aid the heart in pumping blood. Arteries carry oxygenated blood away from the heart to the tissues, except for pulmonary arteries, which carry blood to the lungs for oxygenation.  There are two unique arteries. The pulmonary artery carries blood from the heart to the lungs, where it receives oxygen. It is unique because the blood in it is not "oxygenated", as it has not yet passed through the lungs. The other unique artery is the umbilical artery, which carries deoxygenated blood from a fetus to its mother. Arteries

6. Veins Veins  are blood vessels that carry blood toward the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are the pulmonary and umbilical veins, both of which carry oxygenated blood to the heart. In contrast to veins, arteries carry blood away from the heart. Veins are less muscular than arteries and are often closer to the skin. There are valves in most veins to prevent backflow. The largest veins in the human body are the  venae cavae . These are two large veins which enter the right atrium of the heart from above and below.

7. 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 is the upper chamber of the right side of the heart. 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 different organs of the body.

8. The circulatory system of the lungs is the portion of the cardiovascular system in which oxygen-depleted blood is pumped away from the heart, via the pulmonary artery, to the lungs and returned, oxygenated, to the heart via the pulmonary vein. Oxygen deprived blood from the superior and inferior vena cava enters the right atrium of the heart and flows through the tricuspid valve (right atrio -ventricular valve) into the right ventricle, from which it is then pumped through the pulmonary semilunar valve into the pulmonary artery to the lungs. Gas exchange occurs in the lungs, whereby CO 2  is released from the blood, and oxygen is absorbed. The pulmonary vein returns the now oxygen-rich blood to the left atrium. A separate system known as the bronchial circulation supplies blood to the tissue of the larger airways of the lung. lungs

9. How circulatory system works???? Blood circulation starts when the heart relaxes between two heartbeats: blood flows from both  atria  (the upper two chambers of the heart) into the ventricles (the lower two chambers) which then expand. The following phase is called ejection period , which is when both ventricles pump the blood into the large arteries. In the systemic circulation, the left ventricle pumps oxygen-rich blood into the main artery ( aorta ). The blood travels from the main artery to larger and smaller arteries into the capillary network. There the blood releases oxygen, nutrients and other important substances and takes on carbon dioxide and waste substances. The blood, which is now low in oxygen, is now collected in veins and travels to the right atrium and into the right ventricle.

10. Now pulmonary circulation starts: The right ventricle pumps blood that carries little oxygen  into the  pulmonary artery , which branches off into smaller and smaller arteries and capillaries. The capillaries form a fine network around the pulmonary vesicles , grape-like air sacs at the end of the airways. This is where  carbon dioxide  is released from the blood into the air contained in the pulmonary vesicles and fresh oxygen enters the bloodstream. When we breathe out, carbon dioxide leaves our body. Oxygen-rich blood travels through the  pulmonary vein  and the left atrium into the left ventricle. The next heart beat starts a new cycle of systemic circulation.

11. Causes of poor blood circulation Eating too much junk food which usually leads to being overweight is also a prime reason. Work related issues, such as sitting too long at a computer for years can cause these problems. Especially if you don't take regular breaks or exercise a few times a week There are several medical conditions that slow down or block blood circulation . One of the most dangerous is formation of a blood clot. A blood clot will stop or inhibit blood flow from one part of your body to the remaining areas, causing a stroke or severe damage to your arteries. Other causes of poor blood circulation include Raynaud's Disease, where arteries that supply oxygen-rich blood narrow; heart disease; and deep vein thrombosis..

12. Benefits of proper circulation… Having an increase in blood flow and circulation to areas of your body helps promote cell growth and organ function. Your skin also benefits from an increase in blood circulation. Healthy skin is better able to fight off bacteria and infection that it may come in contact with. When your heart pumps at full force, your heart rate lowers, heart muscles relax and your blood pressure flows evenly and smoothly.