Diffusion of O2 in lungs and muscles

  • High PO2 in lungs, Low PO2 in capillaries
  • High diffusion gradient - increased diffusion rate
  • O2 attaches to haemoglobin which becomes saturated - making oxyhaemoglobin
  • At the muscle O2 dissociates from haemoglobin, attaching to myglobin in the muscle - making oxymyoglobin
HideShow resource information
  • Created by: ellward
  • Created on: 13-11-13 09:19

Cardio respiratory sytem

During exercise:

  • Tidal volume increases
  • Inspiratory reserve volume/ Expiratory reserve volume decrease
  • Breathing rate increases
  • Vital capacity doesnt change
1 of 7

Control of breathing

  • Increase in CO2 and lactic acid - causing decrease in PH
  • Detected by chemoreceptors
  • Sends message to Respiratory control centre in the medulla oblongata
  • Sends message to the nerves
  • Causing cotractions of sternocleidomastoid, scalene and pectoral minor
2 of 7

Hows carbon dioxide carried into the lungs

  • Attaches to haemoglobin
  • Carried in plasma
  • Combines with H2O in plasma making bicarbonate
3 of 7

AVO2 diff increase

  • AVO2 diff - the difference between the amount of oxygen in the blood at the veins and arteries
  • The bigger the difference the more oxygen used
  • The higher the diffusion gradient - increased rate of diffusion
  • Inspiration happens faster
  • More energy created (increase in oxygen)
  • Carbon dioxide removed faster
4 of 7

The respiratory system

  • Nose
  • Mouth
  • Lungs
  • Diaphragm
  • Trachea
  • External Intercostal muscles
5 of 7

Lung volumes during exercise

  • Breathing rate - increases
  • Tidal volume - increases
  • Inspiratory reserve volume - decreases
  • Expiratory reserve volume - decreases
  • Vital capacity - no change
6 of 7

Gas exchange system at the muscles

  • Low PO2 in muscles, High PO2 in cappilaries
  • Larger diffussion gradient - increased rate of diffusion
  • Oxygen dissociates from haemoglobin
  • Oxygen attaches to myoglobin making oxymyoglobin
  • High PCO2 in muscles, Low PCO2 in cappilaries
  • CO2 diffuses from the muscles into the cappillaries
7 of 7


No comments have yet been made

Similar Physical Education resources:

See all Physical Education resources »See all Anatomy & physiology resources »