the mechanics of breathing. breathing breathing change in air pressure in lungs air moves from high...
TRANSCRIPT
![Page 1: THE MECHANICS OF BREATHING. BREATHING Breathing change in air pressure in lungs Air moves from high pressure to low pressure](https://reader035.vdocuments.net/reader035/viewer/2022062422/56649f265503460f94c3e1e4/html5/thumbnails/1.jpg)
THE MECHANICS OF BREATHING
![Page 2: THE MECHANICS OF BREATHING. BREATHING Breathing change in air pressure in lungs Air moves from high pressure to low pressure](https://reader035.vdocuments.net/reader035/viewer/2022062422/56649f265503460f94c3e1e4/html5/thumbnails/2.jpg)
BREATHING
Breathing
• change in air pressure in lungs
• Air moves from high pressure to low pressure
![Page 3: THE MECHANICS OF BREATHING. BREATHING Breathing change in air pressure in lungs Air moves from high pressure to low pressure](https://reader035.vdocuments.net/reader035/viewer/2022062422/56649f265503460f94c3e1e4/html5/thumbnails/3.jpg)
BREATHING
• controlled by two major muscles:
• Intercostal muscles - between ribs
• Diaphragm – below chest cavity
![Page 4: THE MECHANICS OF BREATHING. BREATHING Breathing change in air pressure in lungs Air moves from high pressure to low pressure](https://reader035.vdocuments.net/reader035/viewer/2022062422/56649f265503460f94c3e1e4/html5/thumbnails/4.jpg)
INSPIRATION (INHALING)• diaphragm contracts & moves down• intercostals pull up and out• increases the volume of the chest
cavity• lowers pressure in lungs• air rushes in through nose & mouth to
fill alveoli
![Page 5: THE MECHANICS OF BREATHING. BREATHING Breathing change in air pressure in lungs Air moves from high pressure to low pressure](https://reader035.vdocuments.net/reader035/viewer/2022062422/56649f265503460f94c3e1e4/html5/thumbnails/5.jpg)
EXPIRATION (EXHALING)
• diaphragm and intercostals relax
• ribs are pulled down and inward
• Creates increased pressure in lungs
• air to rushes out• respiratory pearson.notebook
![Page 6: THE MECHANICS OF BREATHING. BREATHING Breathing change in air pressure in lungs Air moves from high pressure to low pressure](https://reader035.vdocuments.net/reader035/viewer/2022062422/56649f265503460f94c3e1e4/html5/thumbnails/6.jpg)
![Page 7: THE MECHANICS OF BREATHING. BREATHING Breathing change in air pressure in lungs Air moves from high pressure to low pressure](https://reader035.vdocuments.net/reader035/viewer/2022062422/56649f265503460f94c3e1e4/html5/thumbnails/7.jpg)
LUNG CAPACITY
• regular breathing does not use the full capacity of lungs
• have reserves for various situation.
![Page 8: THE MECHANICS OF BREATHING. BREATHING Breathing change in air pressure in lungs Air moves from high pressure to low pressure](https://reader035.vdocuments.net/reader035/viewer/2022062422/56649f265503460f94c3e1e4/html5/thumbnails/8.jpg)
LUNG CAPACITY
![Page 9: THE MECHANICS OF BREATHING. BREATHING Breathing change in air pressure in lungs Air moves from high pressure to low pressure](https://reader035.vdocuments.net/reader035/viewer/2022062422/56649f265503460f94c3e1e4/html5/thumbnails/9.jpg)
LUNG CAPACITY
Tidal Volume (TV)– volume of inhaled and exhaled in a normal breath.
Inspiratory Reserve Volume (IRV) – additional volume that can be taken in
Expiratory Reserve Volume (ERV) – additional volume that can be forced out
![Page 10: THE MECHANICS OF BREATHING. BREATHING Breathing change in air pressure in lungs Air moves from high pressure to low pressure](https://reader035.vdocuments.net/reader035/viewer/2022062422/56649f265503460f94c3e1e4/html5/thumbnails/10.jpg)
LUNG CAPACITYVital Capacity (VC) – total volume of gas that can
be moved in or out of the lungs
VC = TV+IRV+ERV
Residual Volume (RV) – amount remaining after a full exhalation
- prevents lungs from collapsing
Total Lung Capacity (TLC) – total volume in lungs at one time
![Page 11: THE MECHANICS OF BREATHING. BREATHING Breathing change in air pressure in lungs Air moves from high pressure to low pressure](https://reader035.vdocuments.net/reader035/viewer/2022062422/56649f265503460f94c3e1e4/html5/thumbnails/11.jpg)
Regulation of Breathing• usually unconscious• brain sends nerve impulse to muscles to
contract/relax
• controlled by CO2 levels in blood
• CO2 diffuses into plasma in blood
• forms H2CO3 in water
![Page 12: THE MECHANICS OF BREATHING. BREATHING Breathing change in air pressure in lungs Air moves from high pressure to low pressure](https://reader035.vdocuments.net/reader035/viewer/2022062422/56649f265503460f94c3e1e4/html5/thumbnails/12.jpg)
• build up of H2CO3 lowers blood pH
• causes brain to send impulse to increase BR so CO2 gets exhaled
Homeostasis – maintaining internal stable conditions