Lung Capacities and the Anatomy and Physiology of the Respiratory System

Abstract Six people were used to measure their inhaling and exhaling volumes. A spirometer was used to “record the volume of all air inhaled and exhaled by the subject” (book. 875).

The six people did four breathing techniques to find their tidal volume, expiratory reserve volume, inspiratory reserve volume and vital capacity. Then calculations were done to find out the MRV, RV and percent predicted VC. Comparing all of the 6 people’s results showed how your health affects your lung capacity. IntroductionThis experiment was performed to show the difference of lung capacities between normal people, athletes, and people who have asthma or are sick. Respiration is “the process by which oxygen is taken up and carbon dioxide is discharged. ” (human) Inhalation is where oxygen comes in through the nose or mouth and travels down the pharynx and into larynx then to the trachea to reach the lungs.

The pharynx is a tube made up of three sections that connects the nasal cavity and the mouth to the larynx. The larynx is made up of cartilage that holds the vocal cords.The larynx has a flap of tissue at the superior end which is what keeps food and water out of the trachea and lungs. The trachea also known as the windpipe is “a tube about ten to twelve centimeters long and two centimeters wide” (human).

“It is supported by 16 to 20 C- shaped rings of hyaline cartilage” (book. 860). The reason that the cartilage does not go all the way around the trachea is so the esophagus can expand when food is being swallowed. The trachea then splits to reach the right and left lung.

Oxygen then fills the lungs.The lungs expand and the diaphragm moves down to allow the lungs more room for expanding. The oxygen is then transported to the aorta to go through the heart and pumped out with the blood to be carried to all the rest of the cells. Expiration is taking the carbon dioxide from the blood and goes through the heart which pumps it into the lungs. The lungs then contract and the diaphragm moves up pushing the carbon dioxide up through the trachea, larynx and pharynx and out through the nose or mouth. The human body needs oxygen to survive without oxygen the brain cannot function and cells will die.

If the respiration process is not working properly it can lead to people having complications with inhaling and or exhaling. This can lead to serious problems. Asthma, smoking, respiratory infections, and how fit a person is can be a factor of how well or poor their breathing is. The amount of oxygen and carbon dioxide a person can inhale or exhale is the respiratory volume level. The tidal volume (TV) is “the amount of air inhaled and exhaled in one cycle of quiet breathing, normally about 500 mL. The inspiratory reserve volume (IRV) is the “amount of air in excess of tidal volume that can be inhaled with maximum effort”.

The opposite of this is expiratory reserve volume (ERV) is the “amount of air in excess of tidal volume that can be exhaled with maximum effort”. The residual volume (RV) is the “amount of air remaining in the lungs after a maximum expiration; the amount that can never voluntarily be exhaled”. (book. 875) The vital capacity is the “amount of air that can be inhaled and then exhaled with maximum effort; the deepest possible breath”.

The vital capacity can be found by the equation: VC=TV+IRV+ERV. Lastly, the minute respiratory volume (MRV) is the “amount of air inhaled per minute”. (book. 876) This lab gives the lung capacities of six people, one normal guy, and one normal girl, one guy athlete, and one girl athlete, one girl with asthma and one girl who is sick. They will all use a spirometer to find their lung capacity.

If the athletes have more lung capacity than normal people, they will definitely have a bigger lung capacity then someone with asthma or who is sick. Materials and Methods Chart, pen or pencil, spirometer, lab bookOn Thursday November 3rd 2011 the experiment began in Cunningham hall. Each person was given a chart to record the results. Six spirometers were given out to the people who volunteered to be the subjects of the experiment.

A spirometer “records the volume of all air inhaled and exhaled by the subject” (book. 875). A cardboard cover was used at the end of the spirometer for sanitary purposes. For each part of the experiment the subject was to stand straight up. The first part of the experiment was to have each of the subjects count their normal respirations per minute.They counted the amount of times they had inhaled or exhaled in a minute.

In order to find the tidal volume the subject inhaled and exhaled normally into the spirometer. This was repeated two more times and the average was used for the final result. Next to find the minute respiratory volume you multiply the tidal volume by the number of respirations per minute. To find the expiratory reserve volume the subject inhaled and exhaled two to three times then forcefully exhaled as much air as possible into the spirometer. This was done two additional times and the average was recorded.Next the vital capacity was found by having the subject breathe in two to three times normally and then bend forward and exhale all of the possible air out.

Then the subject went back to standing upright and inhaled as much air as possible. The subject quickly placed the spirometer in her mouth and exhaled with as much force as she could. This was also repeated twice and the average was recorded. To find the inspiratory reserve volume an equation was necessary because it was not possible to find with the spirometer. The equation used was IRV = VC – (TV + ERV).After this the residual volume was found.

In order to find this the vital capacity was multiplied by a number that is determined by the gender, age and height of the subject which was found in a chart in the lab book. The predicted vital capacity was found by looking at that same chart in the lab book and found the number that coincided with the subject’s gender, age and height. The percent predicted vital capacity was found by taking the result of the vital capacity and dividing it by the predicted vital capacity and then multiplied by 100.This was the end of the experiment and all the numbers were recorded and written on the board for the rest of the class to write down. Results Figure 1 Lung Capacities GroupTVMRVERVVCIRVPredicted VC% Predicted VCRV 150090008502200850312070%550 2850178502467446711504370102%1116.

75 3766. 79967. 11533. 3350012003080113. 63%875 4666133202000495022844533109%750 54004000115030001450316094. 9%750 6500950012002533833312081.

2%633. 25 The data table above shows the lung capacities of six subjects.The first two subjects were normal healthy people, the third and fourth subjects were athletes, the fifth subject had asthma and the sixth subject was sick. Recorded above was the tidal volume, minute respiratory volume, expiratory reserve volume, vital capacity, inspiratory reserve volume, predicted vital capacity, percentage predicted vital capacity and residual volume. Figure 2 Comparing Vital Capacities and the Predicted Vital Capacities The chart above is comparing the VC and predicted VC for all six subject. Normal 1, asthma 5 and Sick 6 are lower than the predicted VC.

While normal 2, athlete 3 and athlete 4 are above the predicted VC.From the experiment the athletes seemed to be above normal but there was also the 2nd normal person whose vital capacity higher than the normal range. I was also confused by normal 1’s results her VC was way lower than what it should be while the person with asthma and the person who was sick were only under the predicted by a little bit. Normal 1’s results were even lower than the person who has asthma and who is sick.

There weren’t any trends or patterns that I could see. Discussion The experiment was done to find out the lung capacities of people who are normal, athletes, someone with asthma and someone who is sick.Comparing all six of the subjects led me to see that my hypothesis was partially right. The two athletes had bigger VC’s then what they should have had.

Also the subject with asthma and the subject who was sick had lower than normal VC capacities. I expected this. What I did not understand was the results of the two normal subjects. Subject 1 had a way lower VC than what should have been, even lower than the one with asthma and the one who was sick, while subject 2 had a VC that was above average, but not by too much. I think somehow the results for subject 1 was incorrect.

Subject 1 may not have followed the directions completely or did not read the numbers correctly on the spirometer. In order to get better results I think we should of repeated the experiments more or redid ones that did not seem correct. Works Cited "Human Respiration. ” Encyclopedia Britannica. Encyclopedia Britannica Online.

Encyclopedia Britannica Inc. ,2011. Web. 15 Nov.

2011. . Saladin, Kenneth S. "The Respiratory System. " Anatomy & Physiology: The Unit of Form and Function. Sixth ed.

McGraw-Hill Companies, 2011. 854-94. Print.