Assignment
Broken Arrow (Respiratory Conduction) Braude, S., Goran, D., and Maxfield, S. 2011.
Case Studies for Understanding the Human Body, 2nd Edition. Boston: Jones Publishers. pp 71-75. Major Viv Deakins, USAF, was not having a good day. His copilot, Riley Hale, kept interfering with Vic's plot to blackmail the government with the nuclear warheads he had just stolen. Riley crashed their $500 million stealth bomber, safely detonated one of the nukes in an abandoned mine. And just kept refusing to die. Deakins just had one nuke, and didn't seem too worried about the helicopter chasing his Hummer through desert canyons. But Pritchett, the guy who bankrolled the whole job, was staring to get on his nerves. Pritchett: You assured me everything would go smoothly. Deakins: Everything is going smoothly, I assure you. Pritchett: It's still my money. Deakins: And if we succeed, you and your friends will get a ton of it. Pritchett: If we're successful? Deakins: Look, Mr. Pritchett, I will deliver the weapon to the destination. But I can't guarantee that those jerks in Washington won't do something stupid like ... not pay. Pritchett: What if they don't? Deakins: Well, if they don't, the Southwest will be a quiet neighborhood for, uh, about 10,000 years. Pritchett: Oh, God! Oh, God! How does the helicopter gunship fit into your well-thought-out strategy? You don't know what you're doing now? This is out of control! I must have been... Deakins was not having a good day and his was out of patience. He steered the Hummer with his left hand, with his right hand, he grabbed the large metal flashlight from the console between the seats. Before Pritchett could finish his whining, Vic extended his arm and whacked him in the throat. Pritchett grasped his neck, gasped for air, and finally shut up. Deakins: Hush. Hush! John Woo. Broken Arrow, 1996, 20th Century Fox.
Task
A. Despicable as his character was, it was hard not to applaud as Deakins (played by John Travolta) shut Pritchett up. Specifically, which part of Pritchett's respiratory tract did he crush?
B. It seems odd that Pritchett was still able to exhale, be he couldn't inhale. When we exhale, does the air push against the walls of the respiratory conducting division or pull in? Is exhalation an active or a passive process?
C. What tissue and structures normally prevent the trachea and bronchial tree from collapsing under the negative pressure of inhalation?
D. Why don't bronchioles need this support?
E. What muscles are responsible for controlling inhalation?
F. The conducting structures are protected from collapsing during inhalation, but the alveoli are at risk of collapsing at the end of exhalation, even in the dry desert. Explain the force that could cause the wet surfaces of the alveoli to stick together, especially at the end of a local vocal outburst, like yelling or crying?
G. Even though he was whining like a baby, Pritchett was an adult and did not have to worry about his alveoli collapsing. What lipoprotein prevents our alveoli from collapsing? Which alveolar cells produce it?
H. Which newborn babies might be at risk of alveolar collapse because they not yet produce this lipoprotein?
I. Pritchett's crushed airway may be a dramatic device in the film, but restricted airways are a very real concern for people who suffer from asthma. One trigger for an asthma attack is irritation of the respiratory tract. Which sorts of airborne particles might cause irritation?
J. Describe how inflammation of the irritated airway would restrict airflow.
K. How does asthma attack further restrict the airflow?
L. What medications are commonly used to treat asthma? How they work to help the person to breathe easier?
M. What function alveolar macrophages serve? What would happen to a person who has a decreased number of alveolar macrophages due to to an immune disease?