B8

Question 1

what are the two gases that are exchanged at the surface of the lungs?

Answer 1

oxygen and carbon dioxide

Question 2

diffusion of gases (oxygen, carbon dioxide)

Answer 2

oxygen and carbon dioxide diffuse from a region of higher concentration to region of lower concentration

Question 3

what should the gas exchange surfaces have?

Answer 3

• large surface area
• very thin surface
• good supply of blood
• well-ventilated with air

Question 4

What do the capillaries do during gas exchange in humans?

Answer 4

Capillary surrounds the surface of each alveolus

blood in capillaries bring carbon dioxide to the gas exchange surface and takes away oxygen to the rest of the body

Question 5

how are gas exchange surfaces adapted for efficient diffusion to take place?

Answer 5

gas exchange surfaces are only one cell thick (gases do not have to diffuse far)
Sphere shape of the surface provides large surface area for diffusion

Question 6

List the structures of the lungs and the route gas exchange takes place in

Answer 6

nose/mouth -> larynx -> trachea -> bronchi -> bronchioles -> alveoli