Maristematic tissue is composed of actively dividing cells. It is located on the growth point in stem tip. Cambium of dicotyledon, and root tip.
Types of Meristematic Tissue
Based on the location
Meristematic tissue can be distinguished into apical, intercalary, and lateral meristems. Apical meristem is located on the tip of rood and stem. Intercalary meristem is located between mature tissues, e.g at the base of nodes in grass stem. Lateral meristem can be found growing laterally with the organ where the tissue is located, e.g. vascular cambium and cork cambium (phelogen).
|The development of stem tip into primary meristem|
Based on the origin
Maristematic tissue can be distinguished into primary and secondary meristems. Primary meristem develops directly from embryonic cells, while secondary meristem develops from differentiated tissues (e.g cambium).
Basically, there are three types of primary meristem as follows.
- Protoderm, which is the outer layer of developing tissues (derived from apical meristem)
- Ground meristem, Which is meristem which form ground tissues.
- Procambium, which is meristem which form vascular tissues.
Cell Characteristics of Meristematic Tissue
Cell the compose meristematis tissue have several acharacteristics as follows.
- Their cell wall is very thin, except on vascular cambium cell wall which is very thick in particular circumstances.
- They consist of a lot of protoplasms which generally do not have food storage and crystal, except on phelogen. Moreover, inside the protoplasm, there are plastid in the form of proplastids.
- Most of apical meristems have small vacuole, only some have larger vacuole (e.g invascular cambium).
source: Biology. The Unity and Diversity of life, 2004