P.E Respiration

• O2 moves from the alveoli in the lungs into the capillaries by diffusion

• deoxgyenated blood is also involved as this is diffusing back into the lungs 

• 21% of gas intaken is O2

• Oxygen attaches to haemoglobin (98%) to become oxyhaemoglobin

• 2% dissolves in plasma

There are many different blood vessels in the body and they all carry blood.

Arteries carry oxygenated blood

Arterioles carry oxygenated blood 

Veins carry deoxygenated blood

Venuoles carry deoxygenates blood 

Capillaires cary both types of blood ( used for diffusion )

                     CO2 detected by the chemoreceptors 

                           Blood pressure is detected by the                                                         baroreceptors 

                        Impulses are send to the medulla

Phrenic nerve                                                        Intercostal nerve

DIaphragm and                                                    abdominal muscle intercostcal nerve

 increase breathing rate                                       increases expiration

Tidal volume - volume of air breathed in or out per breath 

IRV - volume of air that can be foriclbly inspired after a normal breathe

ERV - volume of air that can be forcibly expired after a normal breathe

Residual volume - Volume of air that remains in the lungs after maximum expiration 

Vital capacity - Volume of air forcibly expired after maximum inspiration in one breath 

Minute ventilation - volume of air breathed in or out per minute  

Total lung capacity - vital capacity + residual volume 

Atriovenous difference is the comparison of O2 between arteries and veins 

THis difference increases during exercise because of diffusion and the muscle need more O2 

A-VO2 DIFFERENCE