The two kinds of plant tissue
Plant tissues can be classified on several different criteria. The one used throughout this chapter is the simplest: can these cells still divide?
The criterion
Plant tissues are placed in two main groups according to their ability to divide.
Meristematic tissue
Cells that are still dividing. Region A — A′ of the root tip. The plant grows because of these.
Permanent tissue
Cells that have stopped dividing and specialised for a definite job. Region B — B′. Everything else the plant is made of.
The shape of the rest of this chapter
Plant tissues
- Meristematic — divided further into apical, intercalary and lateral, by where in the plant they sit.
- Permanent — divided into simple and complex, by how many kinds of cell they contain.
Six skills follow, one for each tissue those two branches lead to. The full tree, with every branch filled in, is on the last page of the chapter — worth returning to once the tissues have names.
The two names describe the cells, not the age of the plant
A hundred-year-old tree still has meristematic tissue, at every growing tip and all the way round the trunk — that is how it goes on getting taller and thicker. Permanent is about a cell having settled into a job, not about the plant being old.
One question splits every plant tissue in two
Plant tissues are classified by the ability to divide: meristematic tissue still divides, permanent tissue has stopped and specialised.