Cress: puckered lips

An inconspicuous green cress leaflet reveals many interesting openings on the leaf underside within a scanning electron microscope: the stomata. These pores control the rate of gas exchange. The diameter of the shown stoma is about 8 µm.

The displayed magnification of the scanning electron microscope (SEM) is around 10.000-fold.

The accompanying zoom video:
https://youtu.be/hUm3Q_wocI0