TISSUES
A tissue is a group of cells having a common origin and usually performing a common function.
Types of tissues:
- Meristematic tissue: Growth in plants is largely restricted to specialized regions of active cell division called meristems.
- Permanent tissues: The cells of the permanent tissues do not generally divide further.
TYPES OF TISSUE SYSTEMS
There are three types of tissue systems- epidermal, ground and vascular.
The epidermal tissue systems are made up of epidermal cells, stomata and epidermal appendages.
The ground tissue system forms the main bulk of the plant. It is divided into three zones: cortex, pericycle and pith.
The vascular tissue system is formed by the xylem and phloem, the vascular bundles are of different types. The vascular bundles form the conducting tissue and translocate water, minerals and food material.
MONOCOTYLEDONOUS AND DICOTYLEDONOUS PLANTS
Monocotyledonous and dicotyledonous plants show marked variation in their internal structures. They differ in type, number and location of vascular bundles. The secondary growth occurs in most of the dicotyledonous roots and stems and it increases the girth of the organs by the activity of the vascular cambium and the cork cambium.
WOOD: The wood is a secondary xylem