Monday 9/17/2012

B. Osmosis

Stops:
   1. Isotonic
   2. Cell Bursts
   3. Pressure cancels Osmosis

Water Potential- The potential for H2O to move away from a source. Measured by the equation.
Ψ= Ψ_p + Ψπ
  Ψ=H2O Potential ( measured in Bars)
  Ψ_p=Pressure potential, is always zero or above (always +)
  Ψπ =  Osmotic Potential

Ψπ = -iCRT  (always 0 or negative)
    i= ionization constant (=1because we're working with sucrose) (never negative)
   C = Molar concentration of the solution (never negative)
   R = Pressure Constant (0.0831) (never negative)
   T = Temperature K  (Kelvin) (273+Celsius) can never be negative (never negative)

 Example:
 at time 0 in the cell.
Ψ= 0+ [-(1)(.6)(.08313)(293)
   = 0 + (-14.6)
  = -14.6
Ψ=[-(1)(.2)(.0831)(293)
  = -4.9
-4.9 wants to go into -14.6 until one of the stopping factors occurs.