Gas Exchange

Question 1

Ventilation is

Answer 1

getting air into and out of the lungs

Question 2

Gas exchange is

Answer 2

getting the gases to move into or out of the blood

Question 3

The diffusion of gases in the alveoli depends on three main factors

Answer 3

Large surface area- the larger the surface area the more gas can diffuse.
Short distance - The walls of the alveoli and the blood capillaries are very thin and close together so that diffusion can happen.
Diffusion gradient - gases move faster when there is a bigger difference in concentrations.

Question 4

Alveoli are adapted to carry out gas exchange because…

Answer 4

They have thin, moist walls to let gases pass through. They are surrounded by many blood capillaries and they have an enormous surface area.