Physiology of Organ Systems Essay Example | Topics and Well Written Essays - 1000 words

Physiology of Organ Systems - Essay Example The blood pressure of the arteries increases and decreases with each cycle or stage where the blood passes through the chambers of the heart. Blood enters the heart with a specific sequence or order (National Aeronautics and Space Administration, 2007). The heart also has four valves which control and manage the entry and exit of the blood into and out of the heart. The blood would enter the right atrium through the superior and inferior vena cavae and the right atrium would contract and the tricuspid valve would open and allow blood to enter the right ventricle (NASA, 2007). As the right ventricle contracts, the tricuspid valve closes and simultaneously, the pulmonary valve opens and blood enters the pulmonary artery which brings the blood to the lungs where it is infused with oxygen and eliminates carbon dioxide (Shibao, et.al., 2007). The blood then exits the lungs and enters the left atrium where it is pumped out into the different parts of the body. The blood vessel walls have l ayers of smooth muscle and such muscles as well as the heart muscles are regulated by the autonomic nervous system (Shibao, et.al., 2007). Where there is a decrease in the diameter of the blood vessel, the flow of the blood would be more difficult. The persistent decrease in diameter would increase the pressure needed to push the blood into the different cells of the body. The greater pressure is imposed on the heart which is forcing the blood into the different parts of the body (Lohmeier, et.al., 2004).... The blood would enter the right atrium through the superior and inferior vena cavae and the right atrium would contract and the tricuspid valve would open and allow blood to enter the right ventricle (NASA, 2007). As the right ventricle contracts, the tricuspid valve closes and simultaneously, the pulmonary valve opens and blood enters the pulmonary artery which brings the blood to the lungs where it is infused with oxygen and eliminates carbon dioxide (Shibao, et.al., 2007). The blood then exits the lungs and enters the left atrium where it is pumped out into the different parts of the body. The blood vessel walls have layers of smooth muscle and such muscles as well as the heart muscles are regulated by the autonomic nervous system (Shibao, et.al., 2007). Where there is a decrease in the diameter of the blood vessel, the flow of the blood would be more difficult. The persistent decrease in diameter would increase the pressure needed to push the blood into the different cells of the body. The greater pressure is imposed on the heart which is forcing the blood into the different parts of the body (Lohmeier, et.al., 2004). As the smooth muscles would relax, there is lesser resistance and therefore less pressure needed to maintain the blood flow rates. The autonomic nervous system regulates the diameter of the blood vessels (Lohmeier, et.al., 2004). It also regulates the heart rate, increasing or decreasing it where necessary. With these processes, the autonomic nervous system is able to manage blood pressure. Maintenance of continuous blood flow to the brain and the cells of the body are carried out by the â€Å"regulation of blood pressure by the autonomic nervous system† (NASA, 2007, p. 104). The brain is the receptor of data related to pressure exerted by the