The Cardiovascular System
The heart is one the primary organs in our body. The cardiovascular (CV) system is made up of the heart, the blood and the vessels through which blood travels. The CV system works in sequence with the respiratory system to maintain homeostasis. The heart acts as a pump which move the blood through the blood vessels to the tissues and organs of the body. This allows the CV system to help maintain homeostasis by enabling it to carry out its four major functions. The four major functions of the CV system are transportation of nutrients, gases and waste products, protection from infection and blood loss, maintenance of constant body temperature and maintaining fluid balance within the body.
Arteries, capillaries and veins are major blood vessels. Arterioles are the smaller versions of arteries and they feed the capillaries. Capillaries are where exchange between blood and cells take places. The capillaries gives the cells nutrients, hormones and dissolved gases. The capillaries flush antigens to lymphoid and aid movement of proteins. Excessive capillary pressure causes edema which is excessive fluid. Venules receives the deoxygenated blood from the capillaries and transport it to the veins that brings the blood back to the heart. In a fetus, blood flow skip the lungs which is called pulmonary bypass.
Blood pressure is needed to avoid friction to maintain blood flow. If blood pressure is too low, vessel collapse, blood flow stops and tissue. If it’s too high, vessel walls stiffen and capillary beds may rupture. As you get older you have a decreased hematocrit which is how much space in the blood is occupied by red blood cells. Or it can cause the vessels to be blocked by thrombus (blood clot). Also as you get older you can form varicose veins which are pooling veins in the legs resulting from faulty valves. Valves keep blood flowing towards the heart.
Blood transforms oxygen, carbon dioxide,...
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