Download Lesson 1 Respiratory

Year 10 GCSE PE
A healthy, active lifestyle and your
respiratory system
Learning Objectives
• Do I know the biomechanical aspects of
respiration?
•Do I know the difference between aerobic and
anaerobic respiration?
Starter
On your white boards…
One partner to explain what happens
during inspiration. Breathing in
(mechanics and the composition of air)
One partner to explain what happens
during expiration. Breathing out
(mechanics and the composition of air)
Composition of inspired air
• Oxygen
21%
Oxygen
Nitrogen
Carbon Dioxide
• Nitrogen
78%
• Carbon
Dioxide
0.03%
From your own knowledge…
What do you think the percentages are for
expired air?
• Oxygen?
• Nitrogen?
• Carbon Dioxide?
Composition of expired air
• Oxygen
17%
Oxygen
Nitrogen
Carbon Dioxide
• Nitrogen
78%
• Carbon
Dioxide
4%
• We need oxygen to release energy
• When participating in exercise we need more
• The efficiency of the respiratory system in getting oxygen to the
body will have a big impact on the level of performance achieved
• E.g. ??
•Imagine a 1500m runner who could only walk because he could
not breathe enough oxygen into his body to provide enough
energy to go any faster
Expiration and Inspiration
The movement of the diaphragm and the ribs helps the
movement of air into and out of the lungs.
• During expiration, the
lungs slightly deflate.
• The ribs can move
downwards and
inwards.
• The diaphragm can
relax (move up).
• During inspiration, the
lungs expand to hold
more air.
• The ribs move up and
out.
• The diaphragm
contracts pulling it
tight and flat.
Ventilation Rate
Definition: The number of times we inspire and expire in
one minute.
During exercise the ventilation rate increases:
- an average adult male will inspire and expire
between 10 to 14 times a minute at rest
- this can increase to 25 time a minute during
heavy exercise
Gaseous Exchange
• Oxygen is exchanged from the air into the
blood stream in the alveoli (tiny air sacs).
• Waste carbon dioxide is transferred from
the blood back into the air.
Key Terms
Vital Capacity The maximum amount of air that
can be expired after a maximal inspiration
Tidal Volume Movement of air into and out of the
lungs in one normal breath
Aerobic Respiration
• Respiration is the release of energy from
glucose in the muscles
• When the body is at rest this is aerobic
respiration
• As you exercise you breathe harder and
deeper and heart beats faster to get oxygen
to the muscles
Energy Equation
Glucose + oxygen →
energy + water + carbon
dioxide
Anaerobic Respiration
• When exercising very hard, the heart
cannot get enough oxygen to the muscles.
• Respiration then becomes anaerobic.
Glucose → energy + lactic acid
Anaerobic Respiration
• Anaerobic respiration can only last for a
short period of time.
• Lactic acid is produced.
• The performer will need time to recover
before being able to work at this intensity
again.
• Examples?
Anaerobic Respiration
• During this recovery period will still be breathing heavily even
though they are not working hard.
• This is so they can repay the oxygen debt they have
developed.
Oxygen Debt The amount of oxygen consumed during recovery
above ‘normal’ due to a shortfall of oxygen during activity.
• The additional oxygen is used to restock oxygen levels in the
muscles and help replenish energy store to break down any
lactic acid that has formed.
Homework
• Complete the questions
Plenary
Discuss the following questions in your study buddies –
• What it the energy equation for aerobic respiration?
• What is the energy equation for anaerobic respiration?
• What is oxygen debt?