1) The respiratory system works by inhaling air through the nose and mouth into the lungs. During inhalation, the diaphragm and intercostal muscles contract to expand the lungs and decrease pressure, allowing air to rush in. 2) Gas exchange occurs in the alveoli where oxygen passes into the blood and carbon dioxide passes out of the blood. The air then exits during exhalation through the same process in reverse. 3) Tidal volume and vital capacity can be measured using a spirometer or peak flow meter. Tidal volume is the amount of air inhaled and exhaled during normal breathing, while vital capacity is the maximum amount of air that can be inhaled and

1. GCSE PE
Unit 1.2.3 The respiratory system

2. Start as we mean to go on.....
Can you name the 4 factors that may have an
effect on the cardiovascular system and
increase the risk of heart disease?
1. High Cholesterol
2. Recreational drugs
3. Sedentary lifestyle
4. Stress

3. Today’s learning objectives:
By the end of this lesson you should be able to:
 Explain and understand how the respiratory
system works
Understand tidal volume
Understand vital capacity

4. Starter task…
• Get into groups of 3/4.
• Using the envelopes provided you
need to use your own knowledge to
put the statements in to the correct
order.
• Make sure you read each statement
thoroughly and put it into a logical
sequence.
• Once you have finished make sure
you check that it is right.

5. So did you get it in the right order?
• When breathing in,
• (inhaling)
• the intercostal muscles
• (the muscles between the ribs)
• contract and lift the chest upwards and outwards
• while the diaphragm tightens and lowers.
• (a sheet of muscle which separates the chest
region from the rest of the body cavity)
• These actions open the lungs and create a vacuum
inside so that air (with oxygen) can
• rush in through the nose and mouth, where it is
warmed, moistened and filtered.

6. So did you get it in the right order?
• The air passes through the Trachea
• (the tube that takes air into the chest)
• and into one of the two bronchi into the left or right
lung.
• After passing through the many bronchioles
(smaller tubes) it arrives into
• some of the millions of tiny sacs called alveoli
which are surrounded by
• capillaries (very narrow tubes) that carry blood.

7. So did you get it in the right order?
• Here oxygen, in the alveoli, passes into the blood
so it
• can be transported around the body.
• At the same time waste rich blood releases it’s
• carbon dioxide into the alveoli.
• It takes the opposite journey out of the body;
• exhaled air contains and increased amount of
carbon dioxide.
• The whole process is called
• gaseous exchange.

8. The respiratory system

9. The respiratory system…
Respiratory System

10. So what do we breath in?
Argon Oxygen
Using the table on page ???, Task ???, you need to
to write down what % of each gas is in the air that we
breathe in.
Nitrogen
Follow this by putting the % for each gas that we
breathe out.
Other Carbon
gases Dioxide

11. So what do we breath in?
Argon Oxygen
0.93% 20%
Stays the
same! 16%
Stays the
same!
Nitrogen
4%
79%
Carbon
Other Dioxide
0.04% Stays the
0.03%
same!

12. Tidal Volume
‘is the amount of air inspired and expired with
each normal breath at rest or during exercise’
How do we measure it?
Practical – lets see how we measure it using a
Spirometer
Task 2

13. Vital Capacity
‘is the greatest amount of air that can be
made to pass into and out of the lungs by the
most forceful inspiration and expiration’
How do we measure it?
Practical – lets see how we measure it using a
Peak Flow meter
Task 2

14. Today’s learning objectives:
By the end of this lesson you should be able to:
 Explain and understand how the respiratory
system works
Understand tidal volume
Understand vital capacity

15. Homework
Complete the following:
• Any missing notes from the lesson.
• Hwk 1 Page 2
• Hwk 2 Page 3