April 08, 2015
1.
How much of the chest cavity do the lungs fill? 90%
2.
How many times will the average human breathe in a lifetime?
3.
What happens when we inhale?
lift rib case, lower diaphragm to increase size of chest/descrease pressure
in chest
1.
What happens when we exhale?
relax so chest cavity smaller
How do our nasal passages cope with the dirt we breathe in?
mucus + hair
Why do we get a “runny nose”? excess mucus, cold makes cilia sluggish
April 08, 2015
What is the epiglottis?
How much water do we exhale each day? 1 cup
What reinforces the windpipe?
What 2 things help the windpipe get rid of dirt-filled mucous?
What are alveoli?
How many alveoli do the lungs have?
How much oxygen do the lungs hold?
What signals the brain that we need to breathe?
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16. What do surfactants do to help us breathe? (See p. 329.)
Surfactants are phospholipids. They decrease the elastic recoil in
alveoli, reducing and equalizing the alveoli’s resistance to
inflation. This allows all alveoli to expand equally.
What is elastic recoil? (See p. 328.)
From surface tension of moisture in lungs, makes it hard to inflate
a deflated balloon or alveolus, makes stretched fibers work to
snap back to original unstretched state
17. What do surfactants have to do with “getting the wind
knocked out of you” and with breathing problems in premature
babies?
When we get the “wind knocked out of us,” surfactants reduce
the elastic recoil so we can reinflate our overdeflated lungs.
Surfactants also keep our lungs from completely deflating.
Premature babies haven’t made enough surfactant to decrease
their lungs’ surface tension. This makes it harder for them to
breathe, similar to how hard it is to blow up a deflated balloon.
April 08, 2015
answer summary:
c
2. a 3. d
4. c
6. b
7. c 8. a
9. d (see p. 328)
1.
5. d
10. c 11. a 12. e 13. a
14. d (see p. 335)
15. e
diseases
1. apnea
2. hyperventilation
4. bronchitis
7. tracheotomy
10. TB
5. rhinitis
3. asphyxia
6. sinusitis
8. emphysema
9. asthma