Potassium & STOMATAL OPENING: 2nd Theory Explained

[IneedBioHelp]

Hi,

I need a theory regarding STOMATAL OPENING that involves Potassium. The old theory involves Photosynthesis, but can anyone help me and show me the 2nd theory?

Thanks

 

[IneedBioHelp]

Anyone? Its been like 10 hrs! :(

 

[The Bob]

Maybe no one knows. Would be strange as most people have an area they are good at so just hang in there. Someone might know. smile:

The Bob (2004 ©)

 

[iansmith]

Potassium ions (K+) have been found to play a crucial role in stomatal
movements. The opening and closing of stomata are the results of an active transport of potassium
ions into the guard cells and out of them. The adjacent epidermal cell acts as ion storage cells for
guard cells.
(dark) (Light)
Closure mechanism involves participation of an inhibitor hormone, Abscissic acid (ABA)
which functions in the presence of CO2. In dark, ABA inhibits potassium uptake by changing the
diffusion and permeability of the guard cells. The potassium moves out of the subsidiary cells.
Then, ABA induces the process of acidification in the guard cells, which results in lowering of pH.
At low pH, starch is synthesised leading to closure of stomata.

http://www.tnau.ac.in/notesbscag/notestry/crp201/C%20-4.pdf

 

[IneedBioHelp]

Thanks for the help :)