Science Buddies: "Ask an Expert"

Another year, another science project.
The due dates are closing in fast and I ran into a problem. I finally have been able to find plant stomata with a microscope, but how do I tell if they are opened or closed?

Thanks for the help!

Hi,

That’s a great practical question and I am not sure how you do that. I have looked at stomata under the ‘scope too and at 400x you should be able to see that the pore is open. What kind of ‘scope are you using and at what power?

I googled ‘stoma’ in images and found an article about the opening and closing process that clearly shows the pore in the open and closed position: https://wiki.bio.purdue.edu/biol13100/i ... es_stomata

My question would be, what is the effect of cutting the leaf off the plant and putting it under the scope on whether the stomata are open or closed? Since these cells are responsive to light, gases, moisture, pressure, etc., it is possible that cutting a leaf off a plant could cause them to close.

I have no idea how rapid this opening-closing is, but if you could take the microscope to the plant and observe the stomata without changing anything about the leaf, that would be the best way to do it.

If you have a camera that has high resolution—in the 20 to 30 megapixel range, you could try taking a close-up photo of the leaf on the plant and then enlarging it. You would need to support the camera on a tripod and make sure that the leaf did not move during the photo. I have gotten some great macro photos this way but I don’t know if it would be possible to image something as small as a stoma. It would make a great addition to your science project if you could do it.

I don’t know if this answers your question, but please post back to us if you want more help.

Good luck!

Sybee

Hello,

I have done an experiment looking at stomata before. I peeled off the cuticle layer and used it to apply different chemicals to see what they did to the opening/closing of the stomata. I measured the opening of the stomata under the microscope for each of the different chemicals and did statistical analyses to see if they were significantly different.

Hope that helped! Let us know if you have any more questions.