Have you ever felt your heart racing before a big exam? How about after running a marathon? That fast, steady pace, making you breathe heavily. This is part of your cardiovascular system. A larger system made up of your heart system and circulatory system. The heart works to push out about 5 liters, on average, of blood every minute, to the organs, tissues and cells of the human body. This hard working organ, fully matured is only about the size of your clenched fist. Each cell produces waste products and carbon dioxide. The hearts job is to deliver oxygen and nutrients through arteries, arterioles and capillaries to those cells and remove the produce. Blood is then returned to the heart through venules and veins. Arteries are responsible for moving blood away from the heart. Within most arteries is oxygen, except the pulmonary arteries, they carry deoxygenated blood away from the heart to the lungs. To be able to withstand higher blood pressure, arterial walls have to be thicker compared to most veins. As they branch off they continue to get smaller, losing their outer layers therefore becoming arterioles. Then they finally end in capillaries. Capillaries are the exchange of gases, nutrients and wastes, a functional unit in the cardiovascular system. Their walls are thin and the blood …show more content…
Once the blood is returned to the heart it enters the systemic circuit where it then transports nutrients, hormones and oxygen to the body starting at the left atrium moving through the left ventricle, onto the arteries and into the capillaries. From here, deoxygenated blood moves back through the capillaries into the veins and returns blood to the heart to start the process all over