To define the following terms: ventiliation, inspiration, expiration, forced expiration, tidal volume, expiratory reserve volume, inspiratory reserve volume, residual volume, vital capacity, forced expiratory volume, minute respiratory volume, surfactant, and pneumothorax. To describe the role of muscles and volume changes in the mechanics of breathing. To understand that the lungs do not contain muscle and that respirations are therefore caused by external forces. To explore the effect of changing airway resistance on breathing. To study the effect of surfactant on lung function.
To examine the factors that cause lung collapse.
To understand the effects of hyperventilation, rebreathing, and breath holding on the CO2 level in the blood.
Activity 1: Measuring Respiratory Volumes
Does expiratory reserve volume include tidal volume? Expiratory reserve volume does not include tidal volume. ERC is the amount of air expelled out of your lungs AFTER tidal expiration. Activity 2: Examining the Effect of Changing Airway Resistance on Respiratory Volumes Radius (mm)FEV1 (ml)Vital Capacity (ml)FEV1 (%)
5.003541 ml4791 ml73.90%
4.502303 ml3143 ml73.27%
4.001422 ml1962 ml72.47%
3.50822 ml1150 ml71.47%
3.00436 ml621 ml70.20%
What happened to the FEV1 (%) as the radius of the airways was decreased? FEV1 (%) will decrease as the airways radius is decreased. If the airway becomes smaller, then the resistance to airflow will increase and FEV1 (%). Activity 3: Examining the Effect of Surfactant
How was the air flow changed with surfactant compared to the baseline run? FEV 1 (5) decreased as the radius of the airway is decreased. Airflow increases when surfactant is applied because resistance to lung inflation has been reduced. Premature infants often have difficulty breathing. Explain why this might be so. Surfactant isn’t produced in premature infants and since it is needed for the lungs to inflate, it is not...