An idea to help explain the Respiratory system.

The respiratory system

Pupils will draw an upside down Y on their sheet. They will add a few extra branches at the end of their Y and try to label the respiratory system

Diffusion

High – Low Pressure – to get the concept over - get students to imagine what happens on the tube during rush hour (people crammed into the carriages (High Pressure) when the doors open.


If there is a smallish cupboard see how many students you can get into the cupboard then shut the door! (High Pressure) open the door!


Relate to the Weather and movement of weather fronts from areas of high to low pressure

 

Pupils can then attempt to draw a diagram showing alveoli and blood capillaries to show movement of gases. Use red for oxygen and blue for CO2.

 

Key Points:

  • Gaseous exchange in the lungs takes place by diffusion
  • Oxygen and Carbon Dioxide move down a concentration gradient from a high concentration to a low concentration
  • Oxygen moves into the blood capillaries from alveoli to oxygenate the working muscles
  • Carbon Dioxide moves from blood capillaries to alveoli to be removed from the body
  • Fresh oxygen is then inhaled back into the alveoli to continue the process