This document outlines objectives and outcomes for understanding the structure of the lungs and gas exchange. The key objectives are to explain the process of breathing, describe the difference between inhaled and exhaled air, describe how alveoli are adapted for gas exchange, and how damaged alveoli can result in less gas exchange. It describes the respiratory system including the lungs and thorax, and explains that oxygen and carbon dioxide are exchanged through breathing. Details are provided about inhaling through the mouth and windpipe into bronchioles and alveoli, and exhaling to remove carbon dioxide, with tasks for students to label diagrams and explain the processes.

1. Being HealthyBeing Healthy
Breathing and the lungsBreathing and the lungs

2. Objectives & OutcomesObjectives & Outcomes
 Objective: Develop understanding of theObjective: Develop understanding of the
structure of the lungs and gas exchange.structure of the lungs and gas exchange.
 Outcomes:Outcomes:

All: Explain the process of breathing (4)All: Explain the process of breathing (4)

Most: Describe the difference between inhaled andMost: Describe the difference between inhaled and
exhaled air (5)exhaled air (5)

Some: Describe how alveoli are adapted for theirSome: Describe how alveoli are adapted for their
purpose (6/7)purpose (6/7)

Extension: Describe how damaged alveoli can resultExtension: Describe how damaged alveoli can result
in less gas exchange (7)in less gas exchange (7)

3. The Respiratory SystemThe Respiratory System
 Gas exchange happens in the lungs.Gas exchange happens in the lungs.
 You have 2 lungs, situated in your upperYou have 2 lungs, situated in your upper
thorax / chestthorax / chest
 Here, oxygen and carbon dioxide areHere, oxygen and carbon dioxide are
exchanged – oxygen is needed for life andexchanged – oxygen is needed for life and
carbon dioxide is got rid of when wecarbon dioxide is got rid of when we
breathe out.breathe out.

4. How do we breathe?How do we breathe?
MouthMouth 
Windpipe/tracheaWindpipe/trachea 
bronchibronchi 
bronchiolesbronchioles 
alveolialveoli 
bloodblood

5. Inhalation
(When we breathe in we inhale)

6. Exhalation
(When we breathe out we exhale)

7. Exchanging gasesExchanging gases

8. The Alveoli
The outside of the alveoli is covered with tiny
blood vessels.
Oxygen makes its way into thousands of special air
sacs collectively called the ALVEOLI.

9. The Alveolus
One of these alveoli is called the ALVEOLUS.
This is where the oxygen is transferred into the blood
and carbon dioxide moves out of the blood.
If all these
alveoli flattened
and spread out
onto the floor,
they would
cover an area
the size of a
tennis court!

10. Comparing inhaled and exhaled air
What are the big differences between inhaled and exhaled air?
How could you test for these?
There is another difference…… …… water vapour.
Inhaled Air
Nitrogen (78%)
Oxygen (20.71%)
Carbon Dioxide (0.1%)
Other
Exhaled Air
Nitrogen (75.5%)
Oxygen (14.6%)
Carbon Dioxide (4%)
Other

11. Lets take a closer look (avi)Lets take a closer look (avi)

12. Backup of as wmv fileBackup of as wmv file

13. aviavi

14. wmvwmv

15. Task 1:Task 1:
 With a partnerWith a partner

Partner A – explain the process of breathingPartner A – explain the process of breathing
in and what gases exchangein and what gases exchange

Partner B – explain the process of breathingPartner B – explain the process of breathing
out and what gases exchangeout and what gases exchange
Be prepared to share your answers with theBe prepared to share your answers with the
class.class.

16. Task 2Task 2
 Label diagram of lungs and indicate whereLabel diagram of lungs and indicate where
oxygen and carbon dioxide exchange inoxygen and carbon dioxide exchange in
the lungs.the lungs.

17. PlenaryPlenary
 Objective: Develop understanding of theObjective: Develop understanding of the
structure of the lungs and gas exchange.structure of the lungs and gas exchange.
 Outcomes:Outcomes:

All: Explain the process of breathing (4)All: Explain the process of breathing (4)

Most: Describe the difference between inhaled andMost: Describe the difference between inhaled and
exhaled air (5)exhaled air (5)

Some: Describe how alveoli are adapted for theirSome: Describe how alveoli are adapted for their
purpose (6/7)purpose (6/7)

Extension: Describe how damaged alveoli can resultExtension: Describe how damaged alveoli can result
in less gas exchange (7)in less gas exchange (7)