The Respiratory System
What this difference between
breathing and respiration
 Students are assigned one of three roles -- lungs, oxygen and
carbon dioxide. Children assigned to be the lungs hold hands to
form two circles with an opening at the top. As the lungs inhale,
children step out to widen the circle, and the students
representing oxygen enter the lungs through the opening at the
top, then pass into the bloodstream under the joined hands in
the circle. As the lungs exhale, the students representing carbon
dioxide enter the circle under the joined hands. The children in
the circle step closer together, forcing the carbon dioxide out of
the openings at the top of the circles. This physical
demonstration helps children understand the breathing process.
 A person inhales and exhales fifteen times a
minute, approximately 20,000 times a day.
 Breathing in, and then out counts as one
breathe.
 In 24 hours they breathe in nearly 2,200
gallons (10,000 liters) of air- enough to fill
30,000 coke cans
 Adult lungs hold nearly six quarts of air.
 It would take about three days to drink this
amount of liquid.
How long can you hold your
breath???
 With a partner in the group sit quietly and
count your breaths for one minute
 using the stopwatch. Then jump in place for
30 seconds and count your
 breaths for another minute. What happened?
Why? Record your answer.
 Busy muscles need more oxygen so you
have to breathe harder and faster to get it.
Measure Chest Cavity
 Feel diaphragm
 . With a partner in your group measure a
relaxed chest with a piece of string.
 Now predict how much longer the string will
be when you take a deep
 breath and cut a second piece of string the
length you think. Use a piece of
 masking tape with your name on it and hang
it on the wall with your relaxed
 Ask your partner to take one deep breath and then exhale while
singing a note. Count seconds from the time the note begins
until it ends to measure each one’s lung capacity. Record your
answer.
 Now take a deep breath and see how long you can whisper
without taking another breath. Try again, this time shouting.
What happens when you whisper? Shout? Record your answer.
 Ask students how much air they think they have in
their lungs? Have them take a deep
 breath and blow into the balloons until they run out of
air holding the balloon afterwards as to not let the air
out.
 Ask them how big is the balloon? Tell them it
contains about half the air in their lungs.
 Blow up your balloon again. Let the air out. Explain
to students that the balloon vibrates, making a loud
noise and when air from their lungs passes over
vocal cords in their throat, the cords vibrate, making
sounds.
Nose/Mouth
Pharynx (Throat)
Larynx
Trachea
Bronchi
Bronchioles
Diaphragm
Alveoli
 1. Main function – exchange gasses between
the body and the environment

A. Body removes carbon dioxide and takes in
oxygen
 2. Respiration – exchange of gasses between
body and the environment
 3. Breathing – Taking in/emitting air
How Respiration Works
 Lungs- two large organs that fill with air and
are emptied in a rhythmic way
How Respiration Works
 1. As you breath in, air enters either the nose
or mouth
 1a. Air passes through pharynx (throat) –
cilia filters air
 2. Air then passes through the larynx – voice
box which contains your vocal cords
 -Epiglottis- Flap of tissue above larynx (closes
off when you swallow)
 3. We then enter the trachea – or windpipe
 4. The trachea extends into two tubes which
lead into the lungs – these are called bronchi
So lets see how this works…
How Respiration Works
 5. The bronchi are broken down into smaller
passageways called bronchioles
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a. think of this as a tree with branches
 6. Air then enters alveoli – tiny sacs at the
end of bronchioles
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A. This is where external respiration takes
place!!!
http://www.youtube.com/watch?v=1J8KFmoyl
Es
External Respiration
 A. External respiration – O2 moves from the
lungs (alveoli) into the blood and CO2 moves
from the blood into the lungs (alveoli)
How Respiration Works
 7. From here, O2 is transferred to capillaries
– tiny vessels that surround each alveolis
 8. A vein takes O2 to the cell
 9. The cell uses O2 for energy. When this
happens CO2 is produced. The body needs
to get rid of CO2. This process is called
internal respiration!
 10. CO2 goes back to lungs through an artery
 11. The same process occurs in reverse!
Internal Respiration
 B. Internal respiration – O2 moves from the
blood into the cell and CO2 moves from the
cell to the blood
Lets put it all together…
 . Air comes in the nose or
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mouth
1. Pharynx
2. Larynx
3. Trachea
4. Bronchi (in lungs)
5. Bronchioles
6. Alveoli (external
respiration)
7. Capillaries
8. Vein
9. Cell (Internal Respiration)
 RED- WITH O2
 BLUE- IS WITHOUT O2
(CO2)
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10. Artery
11. Capillaries
12. Alveoli
13. Bronchioles
14. Bronchi
15. Trachea
16. Larynx
17. Pharynx
. Out nose or mouth
Some more terms…
 1. Pleura – thin mucous membrane film that
covers the lungs
 2. Diaphragm – muscle which separates the
lungs from the abdominal cavity
 3. Cilia – tiny hairs that line the respiratory
tract to filter dust and other bacteria from
inhaled air.