You need to breathe in air to get oxygen for _______________.
You breathe out to get rid of _______________ _______________ - a waste product of _______________.
This is known as GASEOUS EXCHANGE and it occurs in an organ known as the _______________.
These are located in the chest or THORAX and are protected by the _______________.
Below your lungs is a sheet of muscle called the _______________. This and the ribs help you to breathe.
Parts Of The Breathing System.
Functions.
· EXTERNAL INTERCOSTAL MUSCLES - contract to raise the ribs and STERNUM [breast bone].
· INTERNAL INTERCOSTAL MUSCLES - contract to lower the ribs and sternum.
· LUNGS - organ where the exchange of _______________ _______________ [out] and _______________ [in] between the atmosphere and blood capillaries takes place. The lungs are surrounded by a PLEURAL MEMBRANE which acts as a _______________ allowing the easy movement of the lungs against the ribs.
· DIAPHRAGM - muscles _______________ and _______________ to decrease and increase the volume of the _______________. This action allows EXHALATION [breathing _______________] and INHALATION [breathing _______________] to occur respectively.
· BRONCHI [left and right bronchus] - bring inhaled air to the left and right _______________ from the _______________ [wind pipe].
· BRONCHIOLES - finer branches of the bronchi channelling air to the _______________.
· ALVEOLI [air sacs] - Tiny, moist [for oxygen to dissolve] air sacs with very thin walls [easy DIFFUSION]. Gaseous exchange occurs between these air sacs and the blood _______________ of the lungs.
The Mechanism Of Breathing.
BREATHING IN:
1. External intercostal muscles CONTRACT - [moves ribs _______________ and _______________].
2. Diaphragm _______________ - flattens.
3. Volume of thorax _______________.
4. Pressure inside thorax _______________.
5. Air is sucked _______________ the lungs.
BREATHING OUT:
1. Internal intercostal muscles CONTRACT - [moves ribs _______________ and _______________].
2. Diaphragm _______________ - dome-shaped.
3. Volume of thorax _______________.
4. Pressure inside thorax _______________.
5. Air is forced _______________ of the lungs.
Compositions Of Inhaled And Exhaled Air.
Gas
Inhaled Air
Exhaled Air
Oxygen
16%
0.03%
4%
Nitrogen
Water Vapour
Variable
Saturated
Oxygen is used up because it is used in the process of _______________.
_______________ _______________ is produced because it is a waste product of RESPIRATION.
_______________ remains unchanged as it is not involved in chemical reactions.
Water vapour becomes saturated as it is another waste product of RESPIRATION.
Vital Capacity And Tidal Volume.
An adult can take in about 5 LITRES of air with their deepest breath.
At rest, about ½ LITRE of air is breathed in and out.
During exercise an extra 3 LITRES of air can be taken in.
The most air you can breathe out is called your vital capacity.
The volume of air that you breathe out when you are resting is called your tidal volume.
Breathing And Exercise.
When exercise is undertaken the rate and depth of breathing _______________. Why?:-
1. Your _______________ need more _______________ for RESPIRATION
