Functions of the Heart Essays - Anatomy, Circulatory System

Functions of the Heart By: Gabby Bouthot Composition I S. Redmond September 13, 2017 Essay 1 The Functions of the Heart The average rate of a heart beat is seventy-two times per minute, in just one day the heart beats over a hundred thousand times but what some people don't know is the intricate workings that go into this small, fist sized muscle. Understanding how the heart works is not as complicated as some might think, functions of the heart start with the pulmonary circuit, then the systemic circuit , and the processes that these sections of the heart preform are able to happen through the power of the pump. Blood circulates through two pathways in the heart, the pulmonary circuit and the systemic circuit. The pulmonary circuit is the pathway from the heart to the lungs, where the deoxygenated blood becomes oxygenated. Blood is pumped throughout the heart through a process called cardiac cycle. Blood that has been depleted of oxygen enters the heart through two large veins called the vena cava and enters the right atrium. The electrical impulses in the heart "pump" the blood down into the right ventricle through the process of cardiac conduction. Once in the right ventricle, on the next contraction the oxygen depleted blood is sent out of the ventricle and to the lungs through the pulmonary artery. In the lungs the blood becomes oxygenated, once this process is complete the oxygen-rich blood is transported into the left atrium via the pulmonary veins. When the heart contracts again blood is pumped down to the left ventricle. The now oxygen rich blood leaves the le ft ventricle through the aorta. This sends the blood through the systemic circuit which is the process of sending oxygenated blood to the rest of the body through major and minor arteries . The heart is able to pump blood through these circuits through a process of contracting and relaxing the heart muscle. Systole refers to the contraction part of the process while diastole refers to the relaxation in this sequence. This process of cardiac contractions is directed by the nervous system. The vagus nerve stimulates the SA node or the pacemaker of the heart which is located in the upper wall of the right atrium. The cluster of cardiac muscle be tween the atria and ventricles, the atrioventricular node, delays the electrical signals before entering the ventricles so the atria contracts before the ventricles do . When the atria contr acts it sends impulse to the Bundle of His, which sends an impulse to the ventricle walls causing a contraction. The heart works hard to keep pumping and a lot goes in to this small muscle in order to keep a person alive. Every minute the heart pumps 1.5 gallons of blood to keep the body stable and in working condition. Keeping the heart healthy will allow these individual functions to continue working, as they should.