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is there someone who has a second kind enough to proof me?
Pretty please?????
Respiratory Physiology
The human respiratory system is a very complex system with the primary function of respiration. Respiration can be broken down further into three functions: 1) ventilation; 2) gas exchange, and 3) oxygen use. Ventilation, otherwise known as external respiration, takes place primarily in the conducting zone. The conducting zone includes the nasal cavity the pharynx, the larynx, the epiglottis, the esophagus, and all other structures air passes through before reaching the respiratory zone. The conducting zone also serves the purposes of warming, humidifying, and filtrating the air. The respiratory zone is where gas exchange and oxygen utilization, also known as internal respiration, take place. The respiratory zone includes the respiratory bronchioles and the terminal alveolar sacs. (Fox, Martini)
In the respiratory system, air is taken in through the nasal cavity, pharynx and larynx, through the trachea and primary bronchi, and into the small bronchioles and alveoli within the lung tissue. The lungs are divided into lobes. The left lung has two lobes: the upper lobe and the lower lobe. The right lung is composed of the upper, the middle and the lower lobes. (The Virtual Autopsy, online)
The process of breathing is largely due to negative pressure in the thorax due to the contraction of the diaphragm. The diaphragm contracts and moves downward, expanding the thoracic cavity. The lungs are held to the thoracic wall by the pleural membranes and low intrapleural pressure (forming a vacuum) and expand with the ribcage and thoracic cavity, causing intrapulmonary pressure to drop below the atmospheric pressure and causing air to rush in. The lungs must both be compliant, or able to expand when stretched, and elastic, or able to return to the original state when released, for good respiration to occur. That elasticity of the lungs provides the pressure needed to push air back out of the lungs in natural expiration. In forced expiration, the diaphragm muscle is used to shrink the thoracic cavity again. (Fox, Martini)
The purpose of the first half of this lab exercise was to find the tidal volume, expiratory reserve volume, and inspiratory reserve volume of a subject. Tidal volume is the volume of air inspired or expired during each normal ventilation cycle. Expiratory volume is the maximum volume of air that can be forcefully inhaled at normal exhalation. Inspiratory reserve volume is the maximum volume of air that can be forcefully inhaled after a normal inhalation. With these, it was possible then to determine the vital capacity of the lungs, or the maximum volume of air that can be inhaled after a maximum inhalation. With the vital capacity, it was possible to use a table to determine the total lung capacity and residual volume, or the volume of air remaining in the lungs after a maximum forced exhalation, of the subject. We also used tables to compare the residual volume and vital capacity of our subject with others in her age group to get a general measure of her respiratory health.
To take the required measurements, we used a SP 304 spirometer unit attached to an iWorx/204 unit and laptop with labscribe software, and a healthy nineteen year-old female volunteer. Before we began, we opened labscribe and selected the “Breathing-rest-exercise” settings from the settings file. We calibrated the spirometer and iWorx unit by placing the spirometer on the lab bench and clicking start. There was a zero calibration during the first five seconds of recording, as no air was moving through the flow head at the time. We then, while recording, asked our subject to sit quietly and breathe into the spirometer at a normal and relaxed pace. We asked her to inhale as much as possible, and then exhale as much as possible to establish an “InMax” and “OutMax.”
To measure these after recording, we clicked the two-cursor icon and dragged the cursors apart so at least one breathing cycle was between them. We then used them to measure four of the five breathing cycles from base to peak to find the tidal volume (volume of air in the lungs after a maximum inspiration), and averaged those four out to find an average tidal volume.
We then measured from the top of a tidal volume wave to the top of the forced expiration wave with the cursors to determine the expiratory reserve volume (maximum volume of air that can be forcefully exhaled after normal exhalation). Using the tidal volume, it was also possible to determine the minute respiratory volume of our subject using the formula MRV = TV x respirations per minute. To measure the inspiratory reserve volume (maximum volume of air that can be inhaled after a normal exhalation), we used the cursors to measure from the bottom of a tidal inspiration to the base of the forced inspiration. It should be noted here that IRV can also be computed using the equation IRV = VC – (TV+ERV). With these numbers, we were then able to determine the vital capacity of our subject. To do so, we measured from the top of the forced expiration to the bottom of the forced inspiration, which indicated the total amount of air possible to exhale after a maximum inspiration. Using a table, we determined how normal the vital capacity of our subject was in relation to others in her age group. We also used the factors given in another table in the lab handout to determine the total lung capacity and the residual volume of our subject. (Lab handout)
The average tidal volume of our subject was 0.350L. Expiratory reserve volume was 0.577L or 577ml. We found an ispiratory reserve volume of 1.058L or 1058ml. The vital capacity of our subject was 1.985L or 1985ml. Our subject’s total lung capacity was 2.481L or 2482ml and her residual volume was .496L or 496ml.
The results of this lab were much lower than both the average and what we expected to find. The average expiratory reserve volume is 1000-1200ml, compared with 577ml in our subject. The average inspiratory reserve volume is 2800ml, as well, compared with 1058ml. Our subject’s vital capacity was a mere 44% of the average of 4500ml, and only 55% of the bottom of the normal range, 3600ml. The total lung capacity and residual volume of our subject were also much lower than others in her age group in the class.
We expected some smaller numbers and diminished lung capacity when we started, due to the fact that our subject (the healthiest specimen in our group) also happened to be recovering from a chest cold. We were, however, very surprised at just how greatly her health impacted the results. This information does correspond with the background information provided to us before the experiment. This exercise is helpful in indicating the general respiratory health of our subject, and it did indicate that the respiratory health of our subject was suffering. It was likely that the elasticity of the lung tissue in our subject was more limited than normal due to irritation from infection and an excess of fluid buildup in the entire respiratory system, both upper and lower.
In conclusion we found that a decrease in the elasticity of the lung has an adverse effect on lung health and limits the ability of the lung to move air at its maximum potential.
Bibliography
Fox, Stuart I. Human Physiology, 8th Ed. McGraw Hill 2004
Martini, Frederick H., et Al Human Anatomy, 4th Ed. Benjamin Cummings 2003
The Virtual Autopsy. Verma, Ajay Mark. 2001 Ed. University of Leicester. 11/23/04 http://www.le.ac.uk/pathology/teach/va/anatomy/case2/frmst2.html
Pretty please?????
Respiratory Physiology
The human respiratory system is a very complex system with the primary function of respiration. Respiration can be broken down further into three functions: 1) ventilation; 2) gas exchange, and 3) oxygen use. Ventilation, otherwise known as external respiration, takes place primarily in the conducting zone. The conducting zone includes the nasal cavity the pharynx, the larynx, the epiglottis, the esophagus, and all other structures air passes through before reaching the respiratory zone. The conducting zone also serves the purposes of warming, humidifying, and filtrating the air. The respiratory zone is where gas exchange and oxygen utilization, also known as internal respiration, take place. The respiratory zone includes the respiratory bronchioles and the terminal alveolar sacs. (Fox, Martini)
In the respiratory system, air is taken in through the nasal cavity, pharynx and larynx, through the trachea and primary bronchi, and into the small bronchioles and alveoli within the lung tissue. The lungs are divided into lobes. The left lung has two lobes: the upper lobe and the lower lobe. The right lung is composed of the upper, the middle and the lower lobes. (The Virtual Autopsy, online)
The process of breathing is largely due to negative pressure in the thorax due to the contraction of the diaphragm. The diaphragm contracts and moves downward, expanding the thoracic cavity. The lungs are held to the thoracic wall by the pleural membranes and low intrapleural pressure (forming a vacuum) and expand with the ribcage and thoracic cavity, causing intrapulmonary pressure to drop below the atmospheric pressure and causing air to rush in. The lungs must both be compliant, or able to expand when stretched, and elastic, or able to return to the original state when released, for good respiration to occur. That elasticity of the lungs provides the pressure needed to push air back out of the lungs in natural expiration. In forced expiration, the diaphragm muscle is used to shrink the thoracic cavity again. (Fox, Martini)
The purpose of the first half of this lab exercise was to find the tidal volume, expiratory reserve volume, and inspiratory reserve volume of a subject. Tidal volume is the volume of air inspired or expired during each normal ventilation cycle. Expiratory volume is the maximum volume of air that can be forcefully inhaled at normal exhalation. Inspiratory reserve volume is the maximum volume of air that can be forcefully inhaled after a normal inhalation. With these, it was possible then to determine the vital capacity of the lungs, or the maximum volume of air that can be inhaled after a maximum inhalation. With the vital capacity, it was possible to use a table to determine the total lung capacity and residual volume, or the volume of air remaining in the lungs after a maximum forced exhalation, of the subject. We also used tables to compare the residual volume and vital capacity of our subject with others in her age group to get a general measure of her respiratory health.
To take the required measurements, we used a SP 304 spirometer unit attached to an iWorx/204 unit and laptop with labscribe software, and a healthy nineteen year-old female volunteer. Before we began, we opened labscribe and selected the “Breathing-rest-exercise” settings from the settings file. We calibrated the spirometer and iWorx unit by placing the spirometer on the lab bench and clicking start. There was a zero calibration during the first five seconds of recording, as no air was moving through the flow head at the time. We then, while recording, asked our subject to sit quietly and breathe into the spirometer at a normal and relaxed pace. We asked her to inhale as much as possible, and then exhale as much as possible to establish an “InMax” and “OutMax.”
To measure these after recording, we clicked the two-cursor icon and dragged the cursors apart so at least one breathing cycle was between them. We then used them to measure four of the five breathing cycles from base to peak to find the tidal volume (volume of air in the lungs after a maximum inspiration), and averaged those four out to find an average tidal volume.
We then measured from the top of a tidal volume wave to the top of the forced expiration wave with the cursors to determine the expiratory reserve volume (maximum volume of air that can be forcefully exhaled after normal exhalation). Using the tidal volume, it was also possible to determine the minute respiratory volume of our subject using the formula MRV = TV x respirations per minute. To measure the inspiratory reserve volume (maximum volume of air that can be inhaled after a normal exhalation), we used the cursors to measure from the bottom of a tidal inspiration to the base of the forced inspiration. It should be noted here that IRV can also be computed using the equation IRV = VC – (TV+ERV). With these numbers, we were then able to determine the vital capacity of our subject. To do so, we measured from the top of the forced expiration to the bottom of the forced inspiration, which indicated the total amount of air possible to exhale after a maximum inspiration. Using a table, we determined how normal the vital capacity of our subject was in relation to others in her age group. We also used the factors given in another table in the lab handout to determine the total lung capacity and the residual volume of our subject. (Lab handout)
The average tidal volume of our subject was 0.350L. Expiratory reserve volume was 0.577L or 577ml. We found an ispiratory reserve volume of 1.058L or 1058ml. The vital capacity of our subject was 1.985L or 1985ml. Our subject’s total lung capacity was 2.481L or 2482ml and her residual volume was .496L or 496ml.
The results of this lab were much lower than both the average and what we expected to find. The average expiratory reserve volume is 1000-1200ml, compared with 577ml in our subject. The average inspiratory reserve volume is 2800ml, as well, compared with 1058ml. Our subject’s vital capacity was a mere 44% of the average of 4500ml, and only 55% of the bottom of the normal range, 3600ml. The total lung capacity and residual volume of our subject were also much lower than others in her age group in the class.
We expected some smaller numbers and diminished lung capacity when we started, due to the fact that our subject (the healthiest specimen in our group) also happened to be recovering from a chest cold. We were, however, very surprised at just how greatly her health impacted the results. This information does correspond with the background information provided to us before the experiment. This exercise is helpful in indicating the general respiratory health of our subject, and it did indicate that the respiratory health of our subject was suffering. It was likely that the elasticity of the lung tissue in our subject was more limited than normal due to irritation from infection and an excess of fluid buildup in the entire respiratory system, both upper and lower.
In conclusion we found that a decrease in the elasticity of the lung has an adverse effect on lung health and limits the ability of the lung to move air at its maximum potential.
Bibliography
Fox, Stuart I. Human Physiology, 8th Ed. McGraw Hill 2004
Martini, Frederick H., et Al Human Anatomy, 4th Ed. Benjamin Cummings 2003
The Virtual Autopsy. Verma, Ajay Mark. 2001 Ed. University of Leicester. 11/23/04 http://www.le.ac.uk/pathology/teach/va/anatomy/case2/frmst2.html
