Why are cells small and SA/ volume concept
Diffusion
Movement of molecules from an area of higher concentration to an area of lower concentration. (requires no energy)
When a cell doubles in size what happens?
When a cell doubles in size the volume increases much more then the surface area, which is why large cells cannot receive enough food efficiently for their volume.
Why are cells small?
because they can absorb nutrients much more efficiently. Because they are smaller they can efficiently absorb enough food. Larger cells do not receive enough food for their volume.
Is the rate at which diffusion occurs the same?
yes is occurs at a rate of 1mm: 2 min