Exchanging Substances Flashcards
1
Q
How are exchange surfaces adapted to maximise effectiveness? Give 4 examples.
A
They have a thin membrane, so substances have a short distance to diffuse
They have a large surface area so lots of a substance can diffuse at once.
Exchange surfaces in animals have lots of blood vessels to get stuff in and out of the blood quickly
Gas
2
Q
Where are villi?
A
The inside of the small intestine
3
Q
What is an advantage for villi in digestion?
A
The increase the surface area in a big way so that digested food is absorbed faster in the blood.
4
Q
What features do they have to make them an advantage?
A
A single layer of surface cells
