Question

How do the guard cells regulates opening and closing of stomata pore?

Answer 1

Guard cells help in opening and closing of stomata

When water enters into guard cells they open up and help the stomatal pore to open.

When water is lost by these guard cells, they shrink and make the stomatal pore to be closed.

Thus, this way guard cells help in opening and closing of stomata pore.

Hope it helps!

Answer 2

The opening and closing of the pore is a function of the guard cells. The guard cells swell when water flows into them, causing the stomatal pore to open. Simillarly the pore closes if the guard cells shrink