6.1 Exchange Flashcards
1
Q
Explain what happens to SA:VOL as a cell becomes larger?
A
As organisms become larger their VOL increases out a faster rate then their SA
2
Q
Explain why cell size is limited?
A
Due to it allowing efficient exchange across their body surface
3
Q
Name 3 features of specialised exchange surfaces?
A
- Larger SA relative to VOL of organism
- Very thin so that the diffusion is short and rapid
- A transport system to ensure the movement of the internal medium
4
Q
Define ficks law?
A
Diffusion= SA x difference in concentration/ length of diffusion path