B2.2.1 Flashcards
1
Q
Why is the surface area to volume ratio important
A
A high surface area to volume ratio means that nutrients can diffuse directly into the organism quickly enough to sustain life, as diffusion distances are small.
2
Q
One way to maximise the exchange surfaces for lungs
A
To maximise the rate of diffusion of oxygen into the bloodstream, lungs contain many alveoli. These increase the surface area of the lungs.
3
Q
What do villi do
A
Villi increase the surface area of the intestine wall increases the rate of diffusion.
4
Q
What happens when the required substance has diffused into your body.
A
It must be transported to where it is needed. This is done using transport systems for example in animals it is the circulatory system and in plants its xylem and phloem.
