RESPIRATORY
SYSTEM PACKET
1) Taking in oxygen: The oxygen your body needs has to come from the air- a mixture of many gasses. Your
body doesn’t need the other gasses from the air you inhale (breathe in). When you exhale (breathe out) most
of the other parts of the air leave your body.
Oxygen is needed by your cells to make energy. The process in which your cells use oxygen and sugars to
make energy is called respiration. Respiration is different from breathing. Breathing is just movement of air
into and out of your lungs. But respiration is the process in the cells that uses oxygen from this air. After
respiration happens, your cells release energy that fuels growth and other cell processes.
2) Getting rid of Carbon Dioxide and Water: In addition to energy, respiration makes carbon dioxide and
water. Your respiratory system gets rid of carbon dioxide and some water through your lungs. ***Cup your
hands over your mouth and breathe into your hands. You will feel your hands become moist. This is the water
coming out of your lungs as you exhale (breathe out).
3) Helping systems working together: The respiratory system is just one of your body systems that makes
respiration possible. Respiration could not happen without the digestive and circulatory systems as well. Your
respiratory system brings oxygen into your lungs. Meanwhile, your digestive system absorbs sugars from food.
Then, your circulatory system carries both oxygen and sugars to your cells, where respiration happens.
Function
What happens
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After Reading Questions
1. What are the 3 functions of the respiratory system?

1

2

3
2. Compare and contrast respiration and breathing:
Respiration
Same
Breathing
3. How would respiration in your body cells be affected if your respiratory system did not bring in enough
oxygen?
4. What two things do our lungs exhale (breathe out)?
___________________________ and _____________________________
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Just like food moves from one organ to the next in the digestive system, air moves from one organ to the next
in the respiratory system. As Air goes from the outside environment into the lung, it passes through
these organ structures:
1) Nasal cavity (nose)- Air enters the body through the nose and moves into nasal cavities behind the nose.
Cells in the nasal cavities make mucus. This sticky material moistens the air and keeps the wall from drying
out. Mucus also traps dust and bacteria that try to get in.
The cells in the nasal cavities also have cilia (sil e a) that are tiny hair-like parts that move. They sweep mucus
into the throat, where you swallow it. Stomach acid then destroys the mucus, along with anything trapped
inside it.
2) Pharynx- Next, air enters the pharynx (the throat). The pharynx is shared with another system—the
digestive system. Both the nose and the mouth connect to the pharynx.
3) Trachea- From the pharynx, air moves into the trachea (windpipe). You can feel your trachea if you move
your fingers down the middle of your neck. The trachea feels like a tube with bumps in it. These bumps are
rings of cartilage that strengthen the trachea and keep it open.
The trachea is also covered with cilia and mucus. The cilia in the trachea actually sweep upward, moving
mucus into the pharynx (throat) where it is swallowed. Remember, mucus cleans and moistens the air, like in
the nose. If things irritate the wall of the trachea, you will cough, which sends these particles out of your body.
4) Bronchi- Air moves from the trachea into the bronchi, the passages that move air into the lungs.
5) Lungs- The lungs (there are 2) are the main organs of the respiratory system. As the bronchi go into the
lungs, they divide into smaller and smaller tubes like the branches of a tree. At the end of the smallest tubes of
the bronchi are parts that look like grapes. The “grapes” are the alveoli (al vee o ly), tiny sacs that move
gasses such as oxygen between air and the blood. In the alveoli blood picks up oxygen from the air inhaled.
Carbon dioxide is also dropped off here from the blood so that it can leave through the lungs.
Organ of respiratory system
(in order):
What does it do?
1)
-mucus:
-cilia:
2)
3)
4)
3
5)
-Alveoli:
After Reading Questions
1. The correct order of organs that air travels through when it is breathed into the body is:
a. pharynx, nose, trachea, bronchi.
b. nose, trachea, pharynx, bronchi.
c. nose, pharynx, bronchi, trachea.
d. nose, pharynx, trachea, bronchi.
2. What job do cilia have in the nasal cavity?What job do they have in the trachea?
3. What part of the respiratory system is also part of the digestive system?
4. What does the stomach have to do with mucus from the respiratory system?
5. What might happen if the trachea didn’t have rings of cartilage?
6. What two systems are working in the lungs?
7. How does oxygen get into the alveoli?
8. The process when sugars and oxygen react in cells to make energy is called _______________.
a. exretion.
b. respiration.
c. bronchitis.
d. breathing.
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9. The trachea splits into 2 tubes called the _______________.
a. alveoli.
b. bronchi.
c. Ureters.
d. vocal chords.
10. Dust particles trapped in mucus are swept away by tiny hair-like _alveoli/cilia_.
11. Clusters of air sacs in the lungs (that look like grapes) are called _alveoli/cilia_.
12. Label the diagram of the respiratory system below:
Word bank:
Nasal cavity (nose)
Bronchi
Pharynx
Lungs
Alveoli
Trachea
13. How does the circulatory system work with the respiratory system to get oxygen into the blood?
14. How does the nervous system (especially part of the brain) work with your respiratory system (the lungs)
and your circulatory system (the heart) to control involuntary actions?
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