Understanding Diffusion and Gaseous Exchange

What is diffusion?

• The movement of oxygen only

• Gas moving from a high concentration to a low concentration

• Gas moving from a low concentration to a high concentration

• The movement of carbon dioxide only

What is gaseous exchange?

• The process of breathing in and out

• The exchange of gases in the atmosphere

• The movement of blood through the heart

• The movement of oxygen and carbon dioxide between the alveoli and the capillaries in the lungs

Which of the following is a feature of the alveoli that improves the efficiency gaseous exchange?

• Thick walls

• Dry surface

• Large surface area

• Long diffusion pathway

What is the thickness of the alveoli walls?

• Two cells thick

• Three cells thick

• Four cells thick

• One cell thick

Which of the following surrounds the alveoli to assist in gaseous exchange?

• Veins

• Arteries

• Capillaries

• Nerves

Which where does oxygen diffuse into during gas exchange?

• Blood in the alveoli

• Blood in the capillaries

• Air in the alveoli

• Air in the capillaries

Which where does carbon diffuse into during gas exchange?

• Blood in the alveoli

• Blood in the capillaries

• Air in the alveoli

• Air in the capillaries