October 9, 2014
Due October 16, 2014
Anatomy and Physiology II
Unit 5 Gas Exchange
Explain how the gas laws and the properties of gases affect the gas exchange between the lung, blood, and tissues. The major function of the respiratory system is to provide the body with oxygen and rid the body of carbon dioxide. Gas exchange occurs between blood and alveolar air (external respiration) and between blood and tissues (internal respiration).Gas exchange process depends on properties of gasses. Based upon the Basic properties of Gases; Dalton’s Law states that each gas in a mixture acts independently of the others. They move in a direction dictated by their concentration gradient and result in partial pressure of each gas becoming proportional to its concentration. External Respiration is the gas exchange between blood and the alveoli within the blood capillaries and result in gas moving down the concentration gradient. Internal Respiration is the gas exchange between blood and cells from the systemic capillaries within the heart that cause O2 to move into the blood from the tissues and CO2 in the bodies tissues to move into the blood. Describe how O2 and CO2 are carried in the blood.
The red blood cells carry oxygen from the lungs to the rest of the body tissues. A small amount of oxygen is carried in the plasma as a dissolved gas. Most oxygen carried in the blood is bound to the protein hemoglobin in red blood cells. About 5% of the Carbon Dioxide is left unchanged. The heart basically acts as a central pump that keeps the blood moving around the body. When air is inhaled, it enters the lungs and diffuses through the alveoli; the oxygen binds with the hemoglobin of the red blood cells to form oxyhemoglobin. The blood then enters the pulmonary circulation system, where it gets pumped round to cells that require energy for cellular respiration. Oxygen diffuses out of the red blood cells and carbon dioxide diffuses in making the blood deoxygenated, it then travels back to the lungs and diffuses into the alveoli and is exhaled as the waste product carbon dioxide.