Exchange -Gas Exchange In Humans

Question 1

What is inspiration

Answer 1

Intercostal muscles and diaphragm contract
Rib cage moves upwards and outwards
Diaphragm flattens
Increase volume of thoracic cavity so lung pressure decrease
Air flows down trachae into lungs
This process is active and requires energy

Question 2

What is expiration

Answer 2

Intercostal muscles and diaphragm relax
Rib cage moves downwards and inwards
Volume of Thoracic cavity decreases
Air pressure increase and air is forced down and out the lungs

Question 3

Adaptations of alveoli

Answer 3

Surrounded by capillaries
Thin exchange surface
Epithelium - one cell hick - short diffusion pathway
Large SA so more exchange