1. 19.3 Part 2
Addi, Kalani, & Grace

2. Respiratory Air Volumes & Capacities
Respiratory Volumes –air the enters/leaves the airways & alveoli during a respiratory cycle a. Tidal Volume – air moved in/out of the lungs during a respiratory cycle; 500 mL of air b. Resting Tidal – normal, resting expiration; 500 mL of air c. Inspiratory Reserve – maximum air inhaled; 3,000 mL of air d. Expiratory Reserve –maximum air exhaled; 1,100 mL of air e. Residual Volume – remaining air in lungs after maximum exhale; 1,200 mL of air

4. Respiratory Air Volumes & Capacities
Respiratory Capacities -
Inspiratory Capacity – maximum volume of air that can be inhaled after exhalation of resting tidal volume; 3,500 mL
Functional Residual Capacity - Volume of air that remains after exhalation of resting tidal volume; 2,300 mL
Vital Capacity - Maximum volume of air that can be exhaled after taking the deepest breath possible; 4,600 mL
Total Lung Capacity - Total volume of air that the lungs can hold; 5,800 mL

5. Major Events in Expiration
The diaphragm and external respiratory muscles relax.
Elastic tissues of the lungs, stretched during inspiration, suddenly recoil, and surface tension pulls on alveolar walls.
Tissues recoiling around the lungs increase the intra-alveolar pressure.
Air is forced out of the lungs.

7. Alveolar Ventilation
Minute Ventilation - volume of air moved into the respiratory passages each minute
Equals the tidal volume multiplied by the breathing rate
Exp: 500 mL x 12 breaths per minute = 6,000 mL
Alveolar Ventilation Rate - affects the concentrations of oxygen and carbon dioxide in the alveoli

8. Nonrespiratory Air Movements- air movements other than breathing
Coughing involves taking a deep breath closing the glottis while air is forced against the closure then the glottis open and a blast of air passes upward.
Sneezing is like a cough excpt air is moving upward and is directed into the nasal cavity by depressing the uvula .
Laughing and crying is when when a person takes a breath and releases it in a series of expirations.
Hiccuping is caused by sudden inspiration due to a spasmodic contraction of the diaphragm while the glottis is closed and air striking the vocal folds causing the sound of a hiccup.
Yawning is taking a deep breath.
When speaking air is forced through the larynx causing the vocal cords to vibrate.

9. Respiratory Disorders That Decrease Ventilation
Bronchial Asthma (aka asthma)- an allergic reaction caused by foreign antigens present in the airways (Ex. inhaled pollen or material on dust mites)
In the smaller airways, mucus and edematous secretions triggered by the allergic reaction which irritates smooth muscle causing bronchoconstriction.
Breathing then becomes difficult due to the clogged airways which leads to wheezing. Ex. inhaled pollen or material on dust mites
5%-10% are diagnosed
Caused by genetic and environmental factors
Majority affected are children and teens
Acts up during physical activity
2. Emphysema - degenerative disease that destroys alveolar walls and alveoli
Clusters of small air sacs fuse into larger chambers which decreases the surface area of the alveoli. As a result, the volume of the gases that are exchanged reduces.
While that happens, the alveolar walls lose their flexibility and the capillary networks decline.
It is difficult to exhale due to the lack of elasticity
3%-2% have the condition
It is chronic and most common in people who smoke