Respiratory System Fun Facts
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The right lung is slightly larger than the left.
Hairs in the nose help to clean the air we breathe as well as
warming it.
The highest recorded "sneeze speed" is 165 km per hour.
The surface area of the lungs is roughly the same size as a
tennis court.
The capillaries in the lungs would extend 1,600 kilometers if
placed end to end.
We lose half a liter of water a day through breathing. This is the
water vapor we see when we breathe onto glass.
A person at rest usually breathes between 12 and 15 times a
minute.
Every minute we breathe, we take in 13 pints of air! That is we
breathe about 6.15 liters of air every minute.
The breathing rate is faster in children and women than in men.
Respiratory System
Chapter 13
Anatomy of the Respiratory System
A.
Conduction System
1. Functions:
a) Direct the air- send air to air
sacs (alveoli)
b) Humidify the air – add H2O
vapor to the air (becomes
damp)
c) Purify the air – Mucus filter the
air of irritants and pathogens.
Cilia push mucus to the back of
the throat where it is swallowed
and digested.
d) Warm the air – Network of veins
in back of nasal cavity to bring
closer to body temperature
Anatomy of the Respiratory System
2.
Anatomical structures of conduction
pathway(in order)
a) Nose with nostrils – openings
through which air enters body.
b) Nasal cavity - Olfactory epithelium
located on the top of the cavity
and other mucus and veins
present to clean and warm the air.
Conchae located here, there are
three lobes (increase surface
area) for more effective
purification.
c) Paranasal sinuses – openings in
the skull bones that lighten the
skull and provide resonance
chambers for voice. Also
production site of mucus that
drains into nasal cavity.
Anatomy of the Respiratory System
d. Pharynx – (5 inches)
common passage for
digestive (food) and
respiratory (air) system.
e. Epiglottis – forms the
opening to the larynx.
Will close when you
swallow so food does
not go down into the
respiratory passages.
d.
e.
Larynx – “voice box”, formed
by elastic cartilage. Location
of vocal folds (vocal cords)
that vibrate with expelled air
forming the sounds we make
when we speak. Glottis is
the slit between the vocal
cords.
Trachea – windpipe (4 inches
– down to T5). Lined with
ciliated mucosa to clean,
mucus is swept up to
pharynx where it is
swallowed or spat out. The
cilia are destroyed by
cigarette smoke and other
pollutants.
Tracheotomy
Trauma to the neck area
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Obstructing tumors in the upper
airway
Respiratory failure requiring long-term
mechanical breathing assistance, as in
these cases:
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Spinal cord injury in the neck
area
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Severe lung infection or
inflammation
Injury to the respiratory tract due to
breathing in smoke or steam or
inhaling corrosive substances
Birth defects of the trachea or larynx
Foreign object blocking the trachea or
larynx
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Anatomy of the Respiratory System
h.
i.
Primary bronchii –
Formed when trachea
divide, one branch goes
to each lung. Bronchii
subdivides within the
lung, routing the air
directly to the air sacs
(alveloli).
Lungs – House the
bronchial trees (further
branching). There are 3
lobes in the right lung
and 2 lobes in the left
lung. Apex is just deep
to your clavicle and the
base is by the
diaphragm. The pleural
membranes that
surround are important
for decreasing friction.
Flashcard Warm-up May 16th
 The

Respiratory Conduction System
Trace the pathway of air through the
conduction system until it reaches the alveoli
of the lungs
• Your notes have these structures in order
Anatomy of the Respiratory System
B.
Respiratory Zone
1. Function - area of gas
exchange (oxygen in
and carbon dioxide out)
2. Structures
a) Respiratory
bronchioles – final
branches of bronchi
where the alveoli (air
sacs) are found.
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Alveoli – air sacs, make up
most of the lung tissue.
Composed of a single cell layer
(simple squamous). Sacs are
connected with alveolar pores
provide alternate routes when
some respiratory bronchioles
are blocked. Sacs are
completely surrounded with
capillaries (cobweb),
membranes fuse forming the
air-blood barrier. Oxygen (into
the blood) and carbon dioxide
(into alveoli sacs) move across
this membrane by simple
diffusion (movement from high
to low concentrations).
Anatomy of the Respiratory System
c. Surfactant producing cell – produce a lipid
molecule that coats the inside of the alveoli.
Helps the sac remain “inflated” by decreasing
the surface tension of water.
BIG IDEA
 “Volume
changes lead to pressure
changes, which lead to the flow of gases
to equalize “
 Boyle's
Law: Relationship Between
Pressure and Volume
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• These demonstrations illustrate Boyle's
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of its container. Thus, if you increase the volume of a container, the pressure will
decrease, and if you decrease thevolume of a container, the pressure will increase.
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Law, which states that the
pressure of a gas is inversely proportional to the volume
Intercostal muscles
 Internal
pull rib
cage in
 External
pull rib
cage up
and out
Respiratory Physiology
A.
Pulmonary Ventilation (breathing) – air moving in and
out of the lungs
1. Requires volume changes in the chest cavity, which
alters pressure of the gases in the lungs helping to
move the air out and in.
a. Inspiration – diaphragm (moves inferiorly and
flattens out) and external intercostals contract
this increases the intrapulmonary volume (lung
size increases as chest cavity moves out) this
causes a decrease in pressure inside (like a little
vacuum) and sucks air into the lungs. This will
continue till the intrapulmonary pressure equals
atmospheric pressure.
Respiratory Physiology
b. Expiration – Primarily a passive process as the
diaphragm and external intercostals relax
(return to normal resting length) the
intrapulmonary volume decreases (causing an
increase in pressure – like deflating a float)
when the pressure is higher than atmospheric
pressure air moves out. If there is a narrowing
of the passageways (asthma) or blockage with
mucus (bronchitis or pneumonia), the internal
intercostals are needed to depress the rib cage
and abdominals can move against the
diaphragm
Respiratory Physiology
2. The collapse of the lungs is prevented
due to the intrapleural pressure always
being negative (never equal to
atmospheric pressure). If this were to
occur, such as when there is a puncture
wound to the chest, the lungs will
collapse, atelectasis.
Respiratory Physiology
3. Capacity and movement of
air in the lungs.
a. Tidal volume – amount of air
exchanged during normal
breathing.
b. Spirometer is used to measure
the respiratory capacities of a
person. Deficiencies in
function can be important in
determining respiratory
diseases and the extent of the
damage. For example,
emphysema affects expiration
(ERV) and the residual volume
is higher.
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Stethescope can also be useful for diagnosing potential
problems. Listening for disruptions in bronchial sounds
(air rushing through the tubes) and vesicular sounds (air
filling alveoli) can indicate problems.
FORCEFUL
INSPIRATION
TV + IRV+ ERV=
FORCEFUL
EXPIRATION
Air that is left in lungs
Respiratory Physiology
B. External Respiration – exchange of gases
between the alveoli and the capillaries.
1. There is always a higher concentration of
oxygen in the alveoli and therefore the
oxygen diffuses passively into the capillary
blood and binds to hemoglobin, turning the
dark red blood of the pulmonary circuit to a
brighter red color for its return trip to the
heart and distribution to the systemic circuit.
Respiratory Physiology
2. Carbon dioxide is at a higher
concentration in the blood as
compared to the alveoli, so
this gas also diffuses into the
alveoli. Carbon dioxide is
transported in the blood
plasma as a bicarbonate ion
(HCO3-), this helps maintain
blood pH, but it is converted
to carbonic acid (H2CO3)
before it diffuses out.
 http://video.about.com/asthma/How-
Lungs-Function.htm
 http://www.youtube.com/watch?v=HiT621
PrrO0
Lung Model
 1.
Answer the “Think” questions on 13A-D.
 2. ONE person from your group will get
the ten layers to build your model.
 3. Color and cut out each layer (make sure
you do NOT cut out the star, square and
circle (these will act as a way to connect
each layer)
 Tomorrow we will analyze the structure,
function and things that can disrupt each
layer
Respiratory Physiology
C. Internal Respiration – exchange of gases
between capillaries and body tissues.
This is again primarily a passive
exchange due to different concentration
gradients in the tissue and the blood.
Flashcard Warm-up May 17th
 Describe
the pressure and volume
changes taking place during
INSPIRATION and EXPIRATION
Respiratory Physiology
D. Control of respiration
1. Neural control
a. Respiratory centers in the brain are located in the
medulla and the pons. The medulla sets the
basic rhythm and the pons smoothes out that
rhythm. Normal respiration is about 12-15
breaths per minute.
b. Stretch receptors in the bronchioles help prevent
over inflation of the lungs and can stimulate the
reaction of expiration.
c. If these respiratory centers are overcome with
drugs (morphine, sleeping pills) or alcohol they
will stop and death occurs.
Respiratory Physiology
2. Other controls
a. Physical factors – exercise can increase rate
and depth of breathing, also increased body
temperature can increase rate and depth of
breathing.
b. Volition - conscious control, necessary for
swimming, singing, swallowing., but when
oxygen gets too low involuntary controls kick
in. (controlled in CORTEX of brain)
world record for breath holding- 19 mins)
Mammalian diving reflex- allows mammals to
hold their breath longer when we are in cold
water
Respiratory Physiology
c. Changes in blood pH due to carbon dioxide
levels. This level is the most important
stimulus for breathing in a healthy person.
1. If CO2 levels decrease, this RAISES the pH (too
basic) of the blood leading to hyperventilation (rapid
respiratory rate) which expels more carbon dioxide.
2. If CO2 levels are too high, this LOWERS pH (too
acid ) hypoventilation (slow, shallow breathing
occurs), keeping more CO2 in the blood.
Respiratory Physiology
3. Individuals with disorders that result in
continuous elevated CO2 levels
(emphysema), the low oxygen levels
become the primarily respiratory
stimulus. This is why these patients are
given low levels of oxygen.
Respiratory Physiology
E. Disruptions in respiratory system
1. System is particularly vulnerable to airborne
pathogens and inflammations due to infections. Ex.
tonsillitis, rhinitis.
2. Disorders that block or obstruct the pathways are
grouped together and called chronic obstructive
pulmonary disease (COPD). They typically include
a patient history of smoking which leads to
increased levels of dyspnea (labored breathing),
coughing, frequent infections, hypoxia (lack of
oxygen in the tissues), and ultimately respiratory
failure. These include:
a.
Emphysema – Alveoli enlarge to
the point where the walls can
break through to other alveoli,
this creates inflammation and
fibrosis of the tissue (decreased
air capacity). Lungs are less
elastic and airways can collapse,
increased difficulty exhaling.
Characterized by a barrel chest
due to over inflation of the lungs.
Due to the air retention in the
lungs (problems exhaling) the
oxygen exchange is very efficient
and initially do not suffer from
hypoxia.
b. Chronic bronchitis –
Increased mucus
production to the point
where it pools in the
lower lungs, there is a
decrease in gas
exchange and an
increase risk of lung
infections. Due to the
low efficiency of gas
exchange these
patients are frequently
hypoxic.
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Asthma is a chronic (longterm) lung disease that
inflames and narrows the
airways. Asthma causes
recurring periods of
wheezing (a whistling
sound when you breathe),
chest tightness, shortness
of breath, and coughing.
The coughing often occurs
at night or early in the
morning.
Layers for Lung model
 Ribs
and vertebrae (posterior)
 Ribs and sternum (anterior)
 Mediastinum and diaphragm
 Lungs (includes the pleural membranes)
 Bronchi
 Alveoli
 Pulmonary arteries
 Pulmonary veins
 Heart
Layers for Lung model
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1. Ribs and vertebrae (posterior)
2. Mediastinum and diaphragm
3. Posterior Lungs (includes the pleural membranes)
4. Bronchi
5. Alveoli
6. Pulmonary arteries
7. Pulmonary veins
8. Heart
9. Anterior lungs
10. Ribs and Sternum
Question of the Week
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What is heartburn and is it
bad for me?
One in 10 Americans
experiences this once a
week.
Despite its name,
heartburn has nothing to
do with the heart. Some of
the symptoms, however,
are similar to those of a
heart attack or heart
disease. Heartburn is an
irritation of the esophagus
that is caused by stomach
acid. This can create a
burning discomfort in the
upper abdomen or below
the breast bone.
Development of Respiratory
System
A.
Infancy and Childhood
1. Lungs are filled with fluid as a
fetus and gas exchange in the
placenta.
2. Surfactant is produced (lipid
molecule) to keep the alveolar
sacs expanded (lowers the
surface tension of water). This
compound is not present in high
enough concentrations until 28
to 30 weeks for the infant to
breath on its own. Infants are
not up to full lung capacity until 2
weeks of age
Development of Respiratory
System
a. Infants born with respiratory
distress (IRDS) can be treated
with new equipment that
maintains proper pressure
levels and keeps alveoli
expanded.
b. SIDS – some cases are
believed to be a neural control
problem many seems to be
linked with heart abnormalities.
The following have been linked to a baby's increased risk of
SIDS:
Sleeping on the stomach
Being around cigarette smoke while in the womb or after being
born
Sleeping in the same bed as their parents (co-sleeping)
Soft bedding in the crib
Multiple birth babies (being a twin, triplet, etc.)
Premature birth
Having a brother or sister who had SIDS
Mothers who smoke or use illegal drugs
Being born to a teen mother
Short time period between pregnancies
Late or no prenatal care
Living in poverty situations
Development of Respiratory
System
4.
Respiratory rate is high ~ 40 to
80 per minute.
B. Early childhood and adolescence
1. Respiratory rate will decrease
~ 30 per minute by age 5.
2. Additional alveoli develop and
lungs completely mature. If
individual begins smoking
during this time the alveoli will
not develop and the lungs
never completely mature.
Development of Respiratory
System
Asthma may develop –
chronically inflamed bronchial
passages.
C. Adulthood and Old age
1. Respiratory rate continues
to decrease, the chest
cavity can become rigid
and the lungs less elastic.
Vital capacity decreases to
about 1/3 by age 70.
2. Ciliary movements and
phagocyte activity decrease
which leads to increased
risk of infection.
3.