1. The Respiratory System
Organ Systems

2. Why is this system so important?
Cells need oxygen to survive
We obtain oxygen by breathing.
We rid waste such as carbon dioxide.

3. The basics… Inhalation: breathing in Exhalation: breathing out
What do we breathe in?
What do we breathe out?
Respiration: exchange of gases (oxygen and carbon dioxide) through the body.

5. Mouth and Nose Brings air into the body
Nasal hairs and mucous in nostrils and mouth trap dust and prevents bacteria/pollen from entering the body.
Will moisten and warm the air too.

6. Pharynx Tube-like passageway used by food, liquid, and air.
At the lower end of the pharynx is a flap of tissue called the epiglottis
(covers the trachea during swallowing so that food does not enter the lungs)

7. Trachea Connects the nose/mouth to the lungs directly.
It is made of cartilage and will not collapse.
Lined with more mucous and little hairs (cilia).

8. Lungs (yes, we have 2 of them!)
It is inside your lungs where oxygen enters the blood stream and carbon dioxide is ready to be exhaled.
The lungs can be further broken up into smaller detail…

9. Bronchi (2 bronchus)
Every human has two bronchus (plural bronchi) – one for each lung.
The bronchi are like tree trunks that further branch out to form bronchioles.

10. Bronchioles
Bronchioles are the smaller branches that come from the bronchi.
They are directly attached to air sacs called alveoli.

11. Alveoli
This is where oxygen enters the blood stream and where carbon dioxides leaves it.
It is through a process called diffusion in which oxygen will diffuse into the blood (arteries) around the alveoli after inhalation.
Carbon dioxide will diffuse out of the blood (veins) and back into the alveoli ready to be exhaled.

13. Inhalation involves… Mouth/nose Pharynx Trachea
Bronchi (left bronchus or right bronchus)
Bronchioles
Alveoli
Blood stream

14. Exhalation involves… Blood stream Alveoli Bronchioles Bronchi Trachea
Pharynx
Mouth/nose

15. Diaphragm This is a muscle that assists with breathing.
When it contracts, you ….. (inhale/exhale)
When it relaxes, you ……. (inhale/exhale)

16. Let’s make a lung!

17. 1. Cut the base from your plastic bottle.
2. Cut the neck off of one of your balloons. Stretch the balloon to fit over the open bottom of your plastic bottle. Tape the balloon to the sides of the bottle.
3. Insert the plastic straw into the other balloon. Wrap the rubber band around the neck of the balloon, securing the straw in place.
4. Roll your plasticine into a small ball, approximately two inches in diameter. Make a hole in the centre using a pen or pencil and push the straw through the hole. Insert the straw so that it extends at least 5-10 cm above the plasticine. Press the plasticine around the straw to seal out gaps and air.
5. Place the balloon end of the straw into the top of the water bottle. Use the plasticine to seal the opening. To watch your model in action, pull down and release the balloon at the base of the bottle.

18. Your homework question…
What are some things that can affect the respiratory system?
Thing about everyday activities, food, drinks, medication, drugs etc…

19. Asthma Asthma is quite common in Australia.
It is caused by something in our environment.
It makes the bronchi and bronchioles swell up making it harder for air to pass.
Asthma attacks can be supported by drugs such as Ventolin that relaxes the airways.

20. Smoking
Smoking involves breathing in toxic chemicals and tar into your lungs.
The tar is like honey and will cover the inside of the alveoli – this stops air gas from entering and exiting the bloodstream.
The toxic chemicals in the smoke kill cells, destroying the alveoli and travel into the blood causing more damage throughout the body.
Emphysema is a disease that results from damaged alveoli.