LG 8 area-to-volume cell ratio

All raw materials necessary for metabolism can enter the cell only through its cell membrane. At some point in a cells life its size is too large, and nutrients are not able to travel that far into a cell, fast enough. When the cells size is no longer convenient, and isn't able to supply raw material over the vast volume of the cell it splits into two and both cells grow back to a comfortable size.

LG 8 rate of diffusion

-The greater the difference in concentration between two areas, the greater the rate of diffusion!
-Temperature increases the rate of molecule movement, therefore, increases the rate of diffusion.
-Pressure increases the speed of molecules, therefore, increase the rate of diffusion.

 

LG 8 wicked awesome cell membrane info

FUNCTION OF THE CELL MEMBRANE??
The cell's plasma membrane does not simply form a "sack" to keep the organelles and jelly cytoplasm together. The plasma membrane is a very important structure which functions to allow certain substances (nutrients) to enter or (waste) to leave the cell. It can "pump" other substance into and out of the cell against the concentration gradient or with transport it passively.