Gaseous exchange

Question 1

Where does gaseous exchange take place?

Answer 1

In the alveoli

Question 2

What is the Alveoli?

Answer 2

Tiny air sacks inside the lungs

Question 3

What are the following features that assist in gaseous exchange?

Answer 3

1. The alveoli are covered in tiny capillaries (blood vessels). Gases can pass through the thin walls and travel into the bloodstream. With training this process of gaseous exchange becomes more efficient and therefore improves performance.
2. A large blood supply. An increased red blood cell content increases the amount of oxygen supplied to muscles and other body tissues. Oxygen combines with the red blood cells to forms oxyhaemoglobin. The same haemoglobin also transports carbon dioxide back from the tissues to the lungs.
3. Capillaries very near to alveoli, so diffusion distance is very short.
4. Large surface area of alveoli allows diffusion to take place.
5. Moist thin walls (one cell thick) of the cells promotes quick diffusion.
6. Gases will always move from areas of high concentration to areas of a low concentration.