This short movie shows the elongation growth of 2 dark-grown Arabidopsis seedlings over a 55 hour period (1 image captured each hour). As is typical of dark-grown seedlings, the stem elongates rapidly, the apical hook is retained, the cotyledons remain pressed together, and no chlorophyll is produced. Arabidopsis seedlings are very small and during the rapid phase of elongation shown here, dark-grown Arabidopsis seedlings elongate at about 0.18 mm/hour. During the course of this movie, the seedlings grew about 10 mm.

See light-grown Arabidopsis for comparison