6.8 exchange of gases in lungs

Question 1

describe & explain the 5 features of the alveoli in gas exchange.

Answer 1

1- flattened - squeezes red blood cells & lower distance between alveolar air

2- thin walls - short diffusion distance

3- large SA - rapid diffusion

4- movement of environmental medium - lungs are constantly ventilated & blood circulated by breathing movements & heart pumping so steep concentration gradient is maintained

5- steep concentration gradient