The purpose of the experiment is to determine gas exchange activity in the respiratory system of human. The first lab for comparing the room and breathe temperature was to understand the function of the nasal cavity where the gas passed after an inhalation. The second lab for changing of chest circumference and abdomen circumference between inspiration and expiration was to know how the air moved in and out. The third lab of level of time of bromothymol blue colour change between normal and exercise was to discover the change level of carbon dioxide in the blood between relaxed and exercise. The forth lab of change time of holding breath after deep breath and quick breath was to show level of carbon dioxide change in the blood after deep breath and quick breath. The fifth lab of measuring diameters of the balloon which was blew by normal and force exhalation was to get the vital volume and the vital capacity form the graph of lung volume vs. balloon diameter.
The major function of the respiratory system is gas exchange between the external environment and an organism's circulatory system. In humans, this exchange facilitates oxygenation of the blood with a concomitant removal of carbon dioxide and other gaseous metabolic wastes from the circulation. As gas exchange occurs, the acid-base balance of the body is maintained as part of homeostasis. If proper ventilation is not maintained, two opposing conditions could occur: respiratory acidosis, a life threatening condition, and respiratory alkalosis (West, John B. 1993). That is why people need to understand their mechanism of gas exchange in their respiratory system.
Materials and methods
In the experiment, materials required were a stop watch, a measuring tape, a thermometer, two straws, 25mL of bromthymol blue, two beakers, a balloon, a meter stick, two metric rulers and a bathroom scale. In lab A, the first step was to use thermometer to record the room temperature. And then, the thermometer was held between the lips of the subject which the subject exhaled. At that moment, through the thermometer, the breath temperature could be read and recorded. The last step was to exhale onto a cooled window and to record what happened. In lab B, while the subject was relaxed, to use a tape measured the chest circumference at the fifth rib and the abdomen circumference at the level of the umbilicus as the initial circumference and also recorded those measurements. Next, while the subject had a full inhalation and a full exhalation, results measured and recorded were regarded as the final circumference. After several calculations, changes in circumference were taken. In lab C, there were 25mL of bromthymol blue poured into both two beakers and to record the beginning colour in each beaker was beneficial to compare with the ending colour and observe changes in colour. While the volunteer was relaxed, the volunteer blew into the first beaker through one straw and then observers recorded the ending colour and the time to change colour from the stop watch. After the volunteer did thirty jumping jacks and blew into the second beaker, the ending colour and the time to change colour were recorded. In lab D, sitting down and breathing normally were the condition. After a deep breath, the partner needed to hold it while being timed and another recorded the result. While the partner normalized the breathing’s rate, the job was to record the breath-holding time after twenty-to-thirty-minute quick breath. Finally, the partner returned the breathing normal again. The final result was the breath holding time after a deep breath as before. In lab E, the first job was to stretch a round balloon several times. Then, when the subject inhaled normally and exhaled normally into a balloon, the subject recorded the diameter of the balloon what the two rulers measured. The subject...