Shoot apical meristem of Coleus

Origin of primary tissues

The shoot apex of Coleus showing the apical meristem region where intense cell division is occurring. Cell division and differentiation are also especially noticeable in the protoderm and procambium regions (look into the two young leaves at the top). The leaves of Coleus are opposite and in four ranks.

The pith is growing from the rib meristem. Files of cells are just starting to be apparent. Each consists of paired opposite leaves. Two nodes are apparent. Both the numbers of cells and the amount of elongation determine the final internode length. Note numerous glandular trichomes.