stomata close at night and open during daytime
This comes about due to changes in turgidity as a result of pH changes in guard cells.
In the dark carbon Iv oxide accumulates in the intercellular spaces
This raises concentration of carbonic acid
The pH drops (pH lowered)
Enzymes convert sugar into starch in guard cells
Osmotic pressure in guard cells is lowered
Water moves out of guard cells by osmosis making cells lose turgidity hence become ?accid
The stomata close
During day time there is photosynthesis hence the production of sugar, carbon IV oxide concentration is lowered, pH increases, guard cells become turgid causing stomata to open.
During the day potassium ions concentrate in guard cells, raising their osmotic pressure and causes then to open
In the night the concentration of potassium ions decreases increasing osmotic pressure in guard cells therefore causes stomata to open.
Mohaissack answered the question on October 5, 2017 at 11:41
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