The Circulatory System transports essential nutrients to areas of the body through circulation in the blood and lymph medium. Blood is composed of erythrocytes, leukocytes, platelets, plasma and other trace substances while the lymph medium is composed of mainly leukocytes, fats and proteins. The Respiratory System oversees the utilization of oxygen in the atmosphere and the ejection of waste products, namely carbon dioxide by the process of inhalation and exhalation respectively. Air is 21% oxygen, 78% nitrogen and 1% water vapor and other gaseous elements. Both the Circulatory and Respiratory system work together to produce an efficient transportation system of nutrients to parts of the body.
The Circulatory System consists of the heart, pulmonary circulation and systemic circulation. The autonomic nervous system controls the heart, electrochemical signals are sent to the sinus node to either increase or decrease heart rate, consequently affecting rate of blood pumping around the body. The pulmonary circuit is the flow of deoxygenated blood to the lungs from the pulmonary artery, where it undergoes gas exchange in alveoli to produce oxygenated blood that flows back to the right chambers of heart through the pulmonary vein. The systemic circulation is the flow of oxygenated blood around the body, it exits the heart by the aorta and after oxygen transfer with muscles the deoxygenated blood comes back to the heart through the Vena Cava.
The Respiratory system consists of the trachea, lungs, bronchi, bronchioles (alveoli) and diaphragm. Inhalation is the intake of air from the atmosphere, and exhalation is the expulsion of used air back to the atmosphere. In inhalation, the external intercostal muscles and diaphragm contract to push the ribcage up and out – this lowers the air pressure in the lungs, which then air from the atmosphere rushes in. In exhalation, the intercostal muscles and diaphragm relaxes to pull the ribcage down and in, effectively increasing air pressure in the lungs which causes air to rush out.
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