Download Functions of the Respiratory System

 List some of the major functions of the
respiratory system.
 High School pg 441
 College pg 831
FUNCTIONS OF THE
RESPIRATORY SYSTEM
 Obtain oxygen and remove carbon dioxide.
 Trap particles from incoming air and help control the
temperature and water content of the air
 Produce vocal sounds
 Participate in the sense of smell
 Regulate blood pH
 Respiratory
Mucosa
 Nasal Conchae
 Sinuses
 Pharynx
 Larynx
 Epiglottis
 Trachea
 Bronchi (Primary,
Secondary,
Tertiary)
 Bronchioles
 Alveoli
THE NOSE
 Nasal conchae
 Increase surface area of nasal
passages
RESPIRATORY MUCOSA
 Secrete mucus to filter air
 Blood vessels warm air
CILIA
PHARYNX (THROAT)
 Common passageway for:
 food esophagus
 air larynx
Esophagus
Passageway for food
Trachea
Passageway for air
LARYNX
 Site of sound production
(vocal folds)
 The epiglottis folds over
the opening of trachea,
preventing entry of liquids
or food
LARYNX
TRACHEA- “WINDPIPE”
–C-shaped cartilage rings keep
passageways open
–No cartilage in back of trachea to
allow food to pass through the
esophagus
BRONCHI/BRONCHIOLES
Trachea branches
into the
 right and left primary
bronchi secondary
bronchi tertiary
bronchi and so on…
 Bronchiole: when the
bronchi no longer
have cartilage
BRONCHIOLES LEAD TO ALVEOLI
 Respiratory bronchioles open into passageways called
alveolar ducts that end at alveolar sacs
 High School pg 447 (Respiratory membrane)
 College pg 845
ALVEOLI
 Functional Unit of Respiratory System
 Ideal site for gas exchange
 Extremely thin walls
 Large Surface Area
SURFACE TENSION
 Alveoli attract water molecules
and cause surface tension,
alveoli are harder to inflate and
can actually collapse
 Alveolar cells synthesize
“surfactant” to fight this and
make it easier to inflate the
alveoli.
RESPIRATORY DISTRESS SYNDROME
 Premature babies do not produce sufficient surfactant and
cannot breathe properly.
 Doctors drip synthetic surfactant into their lungs through a tube
and they breath using a ventilator.
 High School pg 448
 College pg 847
 Pulmonary Ventilation
 Air moving into and out of the lungs (breathing)
 External Respiration
 Gas Exchange between the pulmonary blood and alveoli
 External= Exterior
 Internal Respiration
 Gas Exchange between blood and tissue cells
 Internal= Inside
 Exchange of gases between blood and body cells
 An opposite reaction to what occurs in the lungs
 Carbon dioxide diffuses out of tissue to blood (called loading)
 Oxygen diffuses from blood into tissue (called unloading)
Figure 13.11b
Figure 13.10
 Oxygen Into Blood
 O2 in Alveoli > Blood
 Diffuses into blood from alveoli
 Carbon dioxide out of the blood
 CO2 in Blood > Alveoli
 Pulmonary capillary blood gives up carbon dioxide to be exhaled
BREATHING VOCAB
 Ventilation: breathing
 Inspiration: inhalation, breathing in
 Expiration: exhalation, breathing out
The Mechanics of Breathing
High School pg 449
College pg 852
INSPIRATION
1.
Diaphragm and rib
muscles
contract, increasing
lung volume
2.
As lung volume
increases, lung
pressure decreases
3.
Air is drawn down
into the trachea of the
lung and enters the
alveoli, where the
oxygen diffuses into
the blood
EXPIRATION
1.
Diaphragm and rib
muscles relax
2.
Air moves out of
alveoli and up into the
bronchioles, bronchi,
and trachea
3.
Lung volume
decreases as air leaves
nose or mouth,
increasing air pressure
in the chest cavity
THE LUNGS
 Contains Lobes
 Right lung= 3 lobes
 Left Lung= 2 lobes
 Within the “pleural cavity”
 Parietal pleural membrane
 Visceral pleural membrane
 Tidal Volume (TV)
 Inspiratory Reserve Volume (IRV)
 High School
Pgs 452-453
 Expiratory Reserve Volume (ERV)
 Residual Volume
 Inspiratory Capacity
 Functional Residual Capacity (FRC)
 Vital Capacity (VC)
 Total Lung Capacity
 College
Pgs 855 – 856
RESPIRATORY VOLUMES
 Tidal Volume: volume of air entering or leaving during a single
respiratory cycle.
 Inspiratory Reserve Volume: extra air in lungs during forced
inspiration.
 Expiratory Reserve Volume: air that exits during forced
expiration.
 Residual Volume: air left in lungs even after forced expiration.
RESPIRATORY CAPACITIES
 Combining two or more volumes gives us a capacity.
 1) Vital capacity= IRV + TV+ ERV.
 2) Inspiratory capacity= TV+ IRV.
 3) Function residual capacity= ERV+ residual volume.
 4) Total Lung Capacity= VC+ residual volume. (about 5,800
ml)
RESPIRATORY CAPACITIES