1. GCSE PE
Respiratory
System

2. TASK…..
EXPLAIN IN YOUR OWN WORDS HOW THE RESPIRATORY SYSTEM WORKS

3. YOU MUST GIVE REFERENCE TO THE:
THE NOSE
THE LUNGS AND LUNG STRUCTURE
AIR PASSAGES
RIB MOVEMENT
DIAPHRAGM
PRESSURE IN THE LUNGS P130

4. THE NOSE
THE CILIATED EPITHELIUM AND FILM OF MUCUS WHICH LINE THE NASAL PASSAGES HELP TO TRAP DUST AND BACTERIA. THE AIR IS ALSO WARMED BEFORE IT ENTERS THE LUNGS. YOU CAN ALSO SMELL.
THE LUNGS
TWO THIN-WALLED ELASTIC SACKS LYING IN THE THORAX. THEY CAN EXPAND OR COMPRESS BY MOVEMENTS OF THE THORAX. THEY COMMUNICATE WITH THE ATMOSPHERE THROUGH THE WIND-PIPE OR TRACHEA. IN THE LUNGS GASEOUS EXCHANGE TAKES PLACE, SOME OF THE O2 IS ABSORBED AND CO2 FROM THE BLOOD IS RELEASED INTO THE LUNG CAVITIES.
LUNG STRUCTURE – THE TRACHEA DIVIDES INTO 2 BRONCHI WHICH ENTER THE LUNGS AND DIVIDE INTO SMALLER BRANCHES CALLED BRONCHIOLES. THESE DIVIDE FURTHER AND TERMINATE IN A MASS OF THIN-WALLED, PUCH-LIKE AIR SACS OR ALVEOLI.

5. AIR PASSAGES
RINGS OF CARTILAGE KEEP THE TRACHEA AND BONCHI OPEN AND PREVENT THEM CLOSING UP WHEN THE PRESSURE INSIDE FALLS DURING INSPIRATION. THE LINING OF THE AIR PASSAGES IS COVERED WITH CILIA. THEY CONSTANTLY FLIC TO AND FRO. THEREFORE KEEPING THE AIRWAYS CLEAR.
GAS JAR DEMO!

6. EXTRA NOTES
WE BREATH ABOUT 16 TIMES PER MINUTE
IT IS CONTROLLED BY A REGION OF THE BRAIN WHICH IS VERY SENSITIVE TO THE CO2 CONCENTRATION IN THE BLOOD. A RISE IN CO2 WILL INCREASE BREATHING RATE, FOR EXAMPLE DURING EXERCISE. THIS WILL ALSO INCREASE THE AMOUNT OF O2 IN THE BLOOD, SO MEETING THE DEMANDS OF INCREASED TISSUE RESPIRATION.
THE AGE AS WELL AS THE LEVEL OF FITNESS OF THE INDIVIDUAL WILL DECIDE EXACTLY HOW WELL THE RESPIRATORY SYSTEM CAN COPE WITH THE INCREASED DEMAND MADE BY THE MUSCLES.
REGULAR EXERCISE INCREASES LUNG CAPACITY AND ENABLES MORE OXYGEN TO BE TAKEN IN WITH EACH BREATH.

7. What happens to the air you breath?2. 3.

8. 4. 5. 6.

9. Respiratory Video

10. RESPIRATORY: inspiration
Breathing in
Intercostals & diaphragm contract.
Ribs are pull upwards & down to make chest cavity larger.
Air is pushed into the lungs by the air pressure outside.

11. RESPIRATORY: expiration
Breathing out.
Intercostals & diaphragm relax to make chest cavity smaller.
Lungs are squeezed & air is forced out.

12. RESPIRATORY: anaerobic
Anaerobic energy= no oxygen.
Actions that require a single max effort, over a short period of time.
Demand for oxygen is so great that the body doesn’t have time to supply for the demand.

13. RESPIRATORY: anaerobic
If the demand continues over a minute, LACTIC ACID is produced.
This eventually will cause pain & stop the muscles from working.

14. RESPIRATORY: anaerobic
Oxygen removes lactic acid.
After a short burst of energy, you need extra oxygen to remove the lactic acid.
Extra oxygen is called “Oxygen Debt”
All available oxygen has been used up, so you need to repay the body by breathing deeply.

15. Oxygen Debt
Following high intensity anaerobic exercise where the respiratory and circulatory systems are unable to keep muscles supplied with sufficient oxygen.
The levels of lactic acid rise rapidly and other waste products build up.
Can cause pain in the muscles and rapid state of breathlessness.
Extra Oxygen is needed to oxidise the lactic acid and to restore the resting levels of Oxygen supplies within muscle cells.
This is known as the ‘Oxygen Debt’.
The heavy breathing which continues after the completion of exercise is a clear sign of an oxygen debt being paid back.
If the concentration of lactic acid reaches a certain level, it poisons the cells and cramp occurs.

16. RESPIRATORY: anaerobic
Oxygen turns lactic acid into carbon dioxide.
Which is breathed out by the lungs.

17. RESPIRATORY: aerobic Sufficient supply of oxygen is required.
Activities that last over 1 minute.
Eg; 1500m, marathon
Muscles need oxygen to contract & this enters the body through breathing

18. RESPIRATORY: aerobic
In all invasion games a combination of aerobic & anaerobic respiration is required:
Example: football, lasts 90 minutes but there are also short bursts of energy required.

19. RESPIRATORY: how much do we breathe
Tidal volume: amount you breathe in or out with each breath.
Inspiratory capacity: most you can breath in, after breathing out normally.
Expiratory reserve volume: most air you could force out after breathing out normally.
Vital capacity: most air you could possibly breathe in or out in 1 breath.
Residual volume: amount of air left in your lungs after you’ve breathed out as much as possible.

20. RESPIRATORY: short term effect of exercise.
Gaseous exchange speeds up.
Breathe fast & deeper
More CO² passes out and more O² passes into the blood.
Level of CO² rises
Cell respiration increases

21. RESPIRATORY: long term effects of exercise
The rib muscles and diaphragm grow stronger
More alveloi are available for gaseous exchange
More O² is picked up at each breath & more CO² removed
More capillaries grow around the alveloi, so more blood gets carried around them
Lungs expand further, taking in more air with each breath
You can move O² to the muscles faster and get rid of CO² faster = less tired during exercise

22. HOMEWORK