The Respiratory
System
Look at each part & see how they go
together and what they look like
Know your
basic parts
Major Function of Resp.
System
 Supply the body with Oxygen
 Dispose of Carbon dioxide
Functional Anatomy –
2 zones
 Respiratory zone:
 Actual site of gas
exchange
 (some exchange Respiratory
bronchioles,
alveolar ducts)
alveoli (major
site)
Functional Anatomy –
2 zones
 Conducting zone:
 Conduits – purify,
humidify, and
warm incoming air
 Include all other
respiratory
passageways
Nose – 5 functions
 Provide airway for
respiration
 Moisten & warm air
 Filter air (mucus & cilia)
(breath in thru nose & out
thru mouth)
 Site of olfactory (smell)
receptors
 Resonating chamber for
sound waves (hold your
nose closed & see how
you sound!)
Cilia & Goblet Cells
Mucus traps the
“junk” and the
cilia sweeps it
up toward your
throat so you
can swallow it
or spit it out.
Smoking kills
cilia so
smoker’s
constantly have
to cough to
clear the mucus
out!
Cold day = Runny nose
 The cilia in your nose become sluggish &
slow when they are cold & do not move
the mucus down into your throat
 Mucus in the nasal cavity accumulates &
dribbles out
Nasal Conchae
 Nasal Conchae aka.
NasalTurbinates=
increase SA of
mucosa exposed to
air to help warm &
filter it – also
increase turbulence
(mini tornado effect)
of air – more inhaled
particles swirled onto
mucus and trapped
Nasal Cavity
 Nasal cavity
separated from
oral cavity by the
palate (roof of
mouth)
 Anterior – hard
palate
 Posterior – soft
palate
Paranasal sinuses
functions
 Lighten skull
 Act a resonance chamber
 Produce mucus
Chronic Sinusitis
Check this out! (do not try
this at home or in this
classroom!)
 The Human
Blockhead
Click through the
different pages to see
all the info
Pharynx – 3 basic parts
 Pharynx serves as common passageway
for food (& fluids) and air.
Color code the 3
parts of the pharynx
on the diagram in
your notes
The names give you
location clues!
Pharynx – 3 basic parts
 Nasopharynx – air only
 During swallowing, Soft palate & uvula rise
upward to close off nasopharynx which
prevents food & fluids from entering it
 Oropharynx & Laryngopharynx – food,
liquids & air
 Food will be directed posteriorly to the
esophagus
 Air will go anteriorly into the larynx
Tonsils
(think about the name – it
tells you the location)
 Pharyngeal tonsils: aka. Adenoids –
located in nasopharynx
 Palatine tonsils: located in oropharynx
 Lingual tonsils: located at base of tongue
 All tonsils are lymph nodes & work with
immune system
 You will be labeling these on the back
page diagram
Larynx – 3 Functions
 Provides patent
(open) airway
 Act as a switching
mechanism (between
respiratory &
digestive systems)
 Voice production
(location of vocal
cords)
Adam’s apple
 Know this:
Laryngeal
prominence
on the
thyroid
cartilage
 Seen
externally as
Adam’s
apple
Larynx –
Label diagram on pg 4 now
Epiglottis
 9th cartilage
 When air is flowing into the larynx – free
edge projects upward
 During swallowing:
 Larynx is pulled upward
 Epiglottis is tipped back and down to cover
laryngeal inlet into trachea
 Routes food/fluid into esophagus
Cough Reflex
 Initiated if anything other than air enters the
larynx
 Pressure from air moves object upward out of
the larynx
 Reflex does not work when unconscious so
not a good idea:
 To give fluids to an unconscious person
 Also a reason why people in an alcoholic
coma often die from aspirating their own
vomit.
Trachea (Windpipe)
 The ciliated
mucosa
(mucociliary
escalator)
continuously
propels the mucus
which contains dust
particles and debris
to the throat so it
can be expelled or
swallowed.
Smoking
 Diminishes ciliary activity
 Coughing is ONLY method of preventing
mucus accumulation in the lungs
 Smokers should never be given
medications that INHIBIT the cough
reflex.
Some Effects of Smoking
Reinforcement
 Trachea is reinforced internally by 16-20
C shaped rings (Be able to explain – see
diagram on next slide also)
 Outer portion of C – causes trachea to
stay patent (open) and not collapse
 Inner portion (open part) of C – allow
trachea to be flexible and gives
esophagus a place to expand into upon
swallowing.
Trachea
must be
flexible
yet stay
patent
(open)
 Heimlich
manuver is the
same principle
as a cough
 Used to press
air out of lungs
in case
someone
cannot inhale
to initiate a
cough
Tracheostomy
 -ostomy = cut a hole into
 Used in cases of:





Abnormalities
Cancers
Obstructions
Injuries to area
Etc.
Bronchial Tree
 Trachea divides into right and left primary
bronchi at the level of the sternal angle
(where manubrium and body of sternum
meet).
 Inhaled objects usually lodge in the right
primary bronchus since it is wider,
shorter, and at a more vertical angle
Lungs
 Left lung is smaller, consisting of 2 lobes
and contains a cardiac notch
 Right lung has 3 lobes
 FYI: Bronchopulmonary segments
 Served by own artery, vein, and individual
segmental bronchus
 Left lung has 8 segments while right lung
has 10.
FYI: Important Info
 Respiratory therapists and surgeons use
this info about the different
bronchopulmonary segments so they can
treat the patient as needed
 Even to the point of removing the diseased
segment and leaving the good tissue
 The lungs weigh
approximately 2.5 pounds
Pleurae: Review
 Parietal vs. visceral
 Function of pleural fluid
 Lubricate layers so they can slide across
each other
 Cause them to cling tightly to each other
through surface tension (helps maintain
pressure differences necessary for
inhaling/exhaling)
Respiratory Zone
Structures
 Begins as the
terminal bronchioles
which feed into the
respiratory
bronchioles which
end in the alveoli
chambers where gas
exchange (external
respiration) takes
place.
Alveoli
 Composed of simple squamous – much
thinner than a sheet of paper
 Membrane has gas on one side and
blood on the other.
 Account for the largest portion of lung
volume and provide a tremendous
surface area for gas exchange
Alveoli
 Gas exchanges occur through simple diffusion
 Approximate surface area = 50-70 square
meters (40x greater than skin SA)
 A moist membrane is required so the TYPE II
cuboidal cells secrete a substance called
surfactant that coats the membrane &
interferes with surface tension.
Page 4 diagram
 Use the text book or the internet to label
the head diagram
 Label only the ones that have a dot on
the end.
 Be very specific about the structures.