Biology S3 - Exchanging substances Flashcards
Where does gas exchange happen in the body?
Gas exchange happens in the lungs.
Which gas travels in the lungs?
Oxygen travels into the blood.
Which gas is a waste?
Carbon Dioxide is the waste.
Describe what alveoli are?
Alveoli are air sacs where gas exchange takes place.
Name the process used by oxygen and carbon dioxide to move in and out of the alveoli?
The process used by oxygen and carbon dioxide to move is called diffusion.
List two special features the alveoli have to maximise diffusion.
The alveoli have a large surface area and thin walls to maximise diffusion.
Where in the body are villi found?
Villi are found in the small intestine.
Villi increase the surface area for which process?
Villi increase the surface area for digestion and absorption.
Describe 2 features villi have to help them with their
job.
Villi have a good blood supply and are a single layer of surface cells.
