There are divided into two categories: meristematic and permanent tissue. These tissues can also be divided based on the number of cells that they contain. They are:
- Simple plant tissue: they have one type of cell e.g. parenchyma, collenchymas and seletenchyma
- Complete plant tissue: they are made up of more than one type of cell e.g. zylem and phloem
- Meristematic tissue
It is the origin of most plant tissue, they are made up of undifferentiated cell which are capable of active mitosis cell division
Characteristics of merstematic tissue
- They are small cuboidal thin walled and have a dense cytoplasm with few or no vacuoles
- The tissues do not have intercellular cells because the new cells produced are like those of other growing region
- There are 3 main type of meristem
- Apical meristems
They are responsible of increase in length in plant when mitosis division takes place in them. They are located mainly at the dip of stems and roots
- Lateral meristem
They bring about secondary growth In plants which leads to an increase in the girth. They are located between the xylem and phloem and are called vascular cambium because they give rise to phloem and xylem tissue
- Intercalary meristems
It is located at the base of the internode of young stem and leaves where they actively divide to extend the length of the stem act ward
- Permanent plant tissue
They are made up 3 main categories of tissue which are surface or epidermal tissue, fundamental tissue and vascular tissues
- Surface or epidermal tissue
They form the protective outer covering of flowering plant, it consist of a single layer of outer cells which are irregular in shape. They have the following characteristics:
- Their cells lacks chloroplast
- Their cells have large vacuoles
- They have thick walls with a thin layer of cytoplasm
- They function mainly in protection against water loss mechanical injuries and invasion by bacteria and fungi. They also give rise to structures such as hair, spines, thorns and glands.
