1. Unit 2: Cells and Systems
Topic 3: The Respiratory System

2. Respiratory System
The respiratory system is responsible for Breathing.
It supplies oxygen to your blood through Inhalation
It removes Carbon Dioxide from your blood through Exhaling

3. How Does Breathing Work?
Two major muscles: Diaphragm and Rib Muscles
Inhale
Ribs up
Diaphragm down
Creates a larger space
Less concentration of air inside your body than outside therefore Diffusion causes air to flow into your lungs!

4. How Does Breathing Work?
Two major muscles: Diaphragm and Rib Muscles
Exhale
Diagram goes up
Ribs go down
Decreases the size of chest cavity
Therefore air is forced out of the lungs
How can we prove we breathe out CO2?

5. Raceway through the Respiratory System
1) Nose and Mouth

6. Raceway through the Respiratory System
1) Nose and Mouth
2) Trachea
Tube where air flows into and out of the lungs

7. Raceway through the Respiratory System
1) Nose and Mouth
2) Trachea
Tube where air flows into and out of the lungs

8. Raceway through the Respiratory System
1) Nose and Mouth
2) Trachea
Tube where air flows into and out of the lungs
3) The Bronchi
Tube-like passageways leading off the Trachea and into the lungs

9. Raceway through the Respiratory System
1) Nose and Mouth
2) Trachea
Tube where air flows into and out of the lungs
3) The Bronchi
Tube-like passageways leading off the Trachea and into the lungs
4) The Bronchioles
A more narrow version of Bronchi

10. Raceway through the Respiratory System
1) Nose and Mouth
2) Trachea
Tube where air flows into and out of the lungs
3) The Bronchi
Tube-like passageways leading off the Trachea and into the lungs
4) The Bronchioles
A more narrow version of Bronchi
5) The Alveoli
Tiny air sacks. One cell thick! Over 600 million in your body!
This is where air flows into and out of your blood!

11. Raceway through the Respiratory System

12. A Little More Detail
Alveoli are surrounded by capillaries (tiny blood vessels)
Once Cell thick
This allows for easy diffusion of oxygen and carbon dioxide!
Alveoli Sac
Blood inside Capillary receiving oxygen

13. A Little More Detail
Alveoli are surrounded by capillaries (tiny blood vessels)
Once Cell thick
This allows for easy diffusion of oxygen and carbon dioxide!
Looks pretty neat hey?
Diffusion
Air inside the alveoli has High Oxygen (O2) concentration and low carbon dioxide (CO2 ) concentration
Capillaries in the blood have Low Oxygen (O2) concentration and High carbon dioxide (CO2 ) concentration

14. Discussion Time Why is breathing more difficult at higher altitudes?
Why do some runners train at higher altitudes?
What is the function of alveoli?
What would happen if the alveoli stopped working properly?