Respiratory System
Do Now:
•Why would your
breathing rate increase
from exercising or
from being frightened?
• The lungs produce a detergent-like
substance which reduces the surface
tension of the fluid lining, allowing
• Amazing Lung Facts air in.
• • At rest, a person breathes about 14 to 16 times per
minute. After exercise it could
• increase to over 60 times per minute.
• • New babies at rest breathe between 40 and 50 times
per minute. By age five it
• decreases to around 25 times per minute.
• • The total surface area of the alveoli (tiny air
• sacs in the lungs) is the size of a tennis court.
Nose and Mouth
•Air enters the respiratory
system
•Hollow cavities nasal
passages lined with cilia
•Inhale O2
•Exhale CO2
Pharynx (Throat)
•Air passes from the nose
 pharynx trachea
•Glottisopening to windpipe
•Epiglottis flap of tissue
that covers the glottis when
swallowing
Trachea (Windpipe)
• Connects the nose and the
lungs
• Transports air to the
bronchial tubes.
• Kept open by rings of
cartilage lined with cilia
Bronchial Tubes
•2 Bronchi tubes
•Connects the trachea
to the lungs
Bronchioles
•Smaller tubes of bronchi
•Interacts with the
excretory system to rid
the body of gaseous
waste
Lungs
• Two lungs left and right
lobes
• Covered with a membrane
called pleural membrane
secretes moisture allows
lungs to move
Avleoli
• Moist thin membranes
surrounded by capillaries
• Gas exchange takes place
• O2 body by blood
• CO2 + water vapor into
lungs from blood
Diaphragm
•Muscle located at the
bottom of the chest
cavity.
•Moves rib cage to help
you breathe.
Lungs
•Site of gas exchange in air
sacs called alveoli; O2
goes into the blood, CO2
is removed from the
blood
Lungs
•Interacts with the
circulatory system to
exchange O2 for CO2 in
the blood
Asthma
• Severe allergic reaction
• Causes wheezing, coughing,
breathing difficulty
• Attack bronchioles go into
spasms squeezing air
passages
Bronchitis
• When the lining of the
bronchial tubes are irritated and
swollen
• Passage to alveoli may swell and
clog with mucous
• Causes severe coughing and
hard to breathe
• Common in smokers
Emphysema
• Condition where lungs lose
elasticity in the walls of the
alveoli become damaged.
• Decrease surface area
• Causes shortness of breath
• Smoking increases your risk
• Damage can’t be reversed
Pneumonia
• Condition where the alveoli
are filled with fluid.
• Prevents the exchange of
gases (O2, CO2)
Lung Cancer
•Tumors form in the lungs
•This is a result of
irregular and uncontrolled
cell growth