Figure 2.

Key Events in Stomatal Development Shown in a Dental Impression Series.

The abaxial epidermis of a single cotyledon is shown through time. Cells c (day 7) and f (day 8) are MMCs because they later divided asymmetrically to produce meristemoids. The division of MMC f took place next to a preexisting stoma and produced a satellite meristemoid. Both MMCs arose from smaller, less sinuous cells. One smaller cell (e; day 7) divided symmetrically by day 8. Meristemoid a (day 6) divided twice asymmetrically in an inward spiral. Two apparent meristemoids are adjacent (day 6, lower right); the upper one formed a stoma, but the lower meristemoid (b) did not progress in development (d). Blue, MMC; red, meristemoid; yellow, GMC; green, stoma.