The shoot apex in most dicots produces derivatives which elongate in close proximity to
the apex without much increase in stem diameter. The diameter of the stem can be increased through the action of the Vascular
Cambium. |
 Ti (Cordyline sp.) Shoot Tip: Note the absence of internodal elongation & the increase in stem diameter. |
 Shoot apices in some monocots increase the stem's diameter close the the apical meristem, without any internodal elongation. This is due to the activity of a lateral
meristem known as the Most cells in the PTM divide periclinally (parallel to the surface) to produce files of cells. These do not elongate very much as they expand. This causes an increase in thickness close to the Shoot Apical Meristem. This explains its designation as a "thickening" meristem. |
