Question

write short note on K+ ions concentrated theory for closing and opening stomata​

Answer 1

Answer:

Explanation:according to the recent K+ ion concentration thoery,the stomatal opening and closing depend on the generation of potassium ion(K+).During daytime,tgs chloroplasts in the guard cells photosynthesise which leads to the production of ATP.this ATP is used to actively pump the potassium ions of the adjacent cells into the guarx cells.Increased K+ concentration in the guard cells make them hypertonic so more water from the adjacent cells is drawn in and the cells become more turgid and they bow outwards to open out the stomatal pore.Reverse happens at night The K+ ion leak out thus reducing the turgor of guard cells and the stomatal pore closes.

Answer 2

There are two theories about the opening and closing of stomata:

• Potassium ion concentration theory
• Sugar concentration theory

Potassium ion concentration theory:

This is the recent theory in which ATP is used to actively pump the potassium ions of the adjacent cells into the guard cells.

Sugar concentration theory:

This the old theory in which the guard cells become turgid and bulbs out words due to their thin outer wall, thus widening the stomatal opening lying in between.