procambium การใช้

Cambium and procambium are their main centres of production.
Although it is composed of non-vascular parenchyma cells, it is still considered part of the vascular cylinder because it arises from the procambium as do the vascular tissues it surrounds.
Phloem is produced in phases . " Primary " phloem is laid down by the apical meristem and develops from the procambium . " Secondary " phloem is laid down by the vascular cambium to the inside of the established layer ( s ) of phloem.