Lungs and Gas Exchange B2

Question 1

What is the job of the lungs?

Answer 1

The job of the lungs is to transfer oxygen to the blood and to remove the waste carbon dioxide from it.

Question 2

When we breathe in air where is the first place the air goes to?

Answer 2

The trachea (wind-pipe)

Question 3

When we breathe in air where is the second place the air moves to?

Answer 3

The air divides between the 2 bronchi

Question 4

When we breathe in air where is the third place the air moves to?

Answer 4

It divides from the bronchi to branch like structures called bronchioles.

Question 5

When does the air we breathe in travel to last?

Answer 5

After the air has travelled through all the branches it reaches the small sacs called alveoli which are the site of gas exchange.

Question 6

How are alveoli adapted to their role?

Answer 6

They have a single layer of surface cells like the capillaries next to them to create a short diffusion pathway, they have a large surface area so multiple substances can move at once, they have moist walls that allow gases to dissolve this increases the rate of diffusion.

Question 7

How is the small intestine adapted to their role?

Answer 7

Small intestines are covered in millions of villi which increase the surface area so that food molecules are absorbed much faster. Villi have a single layer of surface cells and a very good blood supply