The Journey Of The Blood Physical Education Essay

The Circulatory System is the main transportation and cooling system for the body, the red blood cells carry oxygen and nutrients to the cells in the body. The circulatory system also contains white blood cells; these blood cells take care of things like infections, cuts and generally clean up the system. The circulatory system is made up of the of blood vessels,blood and the heart , the heart is the circulatory systems power supply

The right atrium is where the process begins, when the blood enters the right atrium which is one of the four chambers in the human heart (two atria and two ventricles) it receives deoxygenated blood (co2) from the superior and inferior vena cava and the coronary sinus. Gravity and a gentle squeeze then help push the blood through the tricuspid valve which is one of four of the hearts valves. Each valve helps to control the flow of blood in the right direction ; it then flows into the right ventricle. The tricuspid valve is made up 3 strong flaps of tissue called leaflets which allows blood to go from the top of the heart to the bottom, this valve closes when the right ventricle contracts, The contracts of the heart are caused by electrical impulses generated by the heart muscle. These impulses begin in the sinoatical node also referred to as the hearts natural pacemaker and cause the heart to contract in turn they regulate the beating of the heart which is its rhythm .The tricuspid valve is one of four of the hearts valves; it is the first valve that blood encounters as it enters the heart. When the blood reaches the right ventricle which is in the lower chamber of the heart it begins the contraction to push the blood out under low pressure towards the lungs. At this point the blood is still deoxygenated; the blood then leaves the right ventricle and enters the pulmonary artery which are formed as terminal branches of the pulmonary trunk. They convey blood to the lungs; its two branches are unique in a way that they are the only arteries in the body that carry blood that is deoxygenated. The blood then enters the capillaries in the lungs; they are the smallest blood vessels in the body and are part of the microcirculation. They are only 1 cell thick these micro vessels, measuring 5-10 micro meters in diameter. They connect the arteries to the veins which enable the exchange of water,oxygen,carbon dioxide and nutriments. They are located against the air sack in the lungs, when the blood cells move past the air sack the red blood cells pick up oxygen and dump the co2. After the blood has been oxygenated it enters the pulmonary veins which are blood vessels. The pulmonary veins take the blood that has been oxygenated back to the heart through the left atrium which is another one of the four chambers in the heart and sits above the left ventricle with the mitral valve separating them both. The mitral valve prevents blood from being pushed from the left ventricle to the left atrium “doing the same function as the tricuspid valve”. The left ventricle is another of the four chambers and has a very high pressure which allows it to push the blood out of the heart and into the body’s circulation. After the blood has left the left ventricle it enters the aorta, which is the biggest blood vessel in the body. It brings oxygenated blood to the body in the systemic circulation; the aorta is an elastic artery and is able to stretch when blood is pumped into it. Allowing it to maintain pressure during contraction, it has valves at the opening to prevent the blood from blocking up and going back into left ventricle. While the blood is in the aorta the corony arteries allows the heart to receive its own supply of blood to all the parts of the heart muscle feeding the heart which is the hardest working muscle in the body, it then leaves the aorta and makes its way to the head, to do this it travels through the aortic arch which is one of a series of paired arteries that connect the ventral arterial system to the dorsal arterial system then it gets distributed throughout the body

THE RESPIRATORY SYSTEM is the Oxygen Delivery System of the body,the main function of the respiratory system is to supply the blood with oxygen in turn allowing the blood to deliver oxygen to all the parts of the body. The respiratory system is able to do this through breathing. When we breathe, we inhale oxygen and exhale carbon dioxide. The exchange of gases is the respiratory system’s means of getting oxygen to the blood. Respiration is achieved through the mouth, nose, trachea, lungs and diaphragm. Oxygen enters the respiratory system through the mouth and nose. The oxygen then passes through the larynx (where speech and sounds are produced) and the trachea which is a tube that enters the chest cavity. In the chest cavity, the trachea splits into two smaller tubes. Called the bronchi, each bronchus then divide’s again forming the bronchial tubes. The bronchial tubes lead directly into the lungs where they divide into many smaller tubes which connect to tiny sacs called aveoli.The average adult’s lungs contain about 600 million of these spongy, air filled sacs that are surrounded by capillaries into the arterial blood.Meanwhile,the waste-rich blood from the veins releases it’s carbon dioxide into the alveoli. The carbon dioxide follows the same path out of the lungs when you exhale. The diaphragms job is to help pump the carbon dioxide out of the lungs and pulls the oxygen into the lungs. The diaphragm is a sheet of muscles that lie across the bottom of the chest cavity as the diaphragm contracts; oxygen is pulled into the lungs. When the diaphragm relaxes, carbon dioxide is pumped out of the lungs