Okay Valerie, the link:
https://en.wikipedia.org/wiki/...
Wiki no longer has the images I saw before regarding guard cells and stoma of a plant leaf. The older better images showed guard cells which to me looked like thousands of little eyes opening and closing,
but actually are similar to mouths. So many of them in a leaf. The guard cells captured my attention more than other cells. Reading
the Wiki article about these will relate how these cells work.
It amazes me to no end.
There is a separate entry on Wiki for stoma and for guard cells.
I couldn't find images in google either that showed what I saw a few
years ago, but there are some that show one to a few in the parameters of the image.
Hope this helps a bit.