Types of tissues in plant

Tissues

           The body of a plant is made up of several kinds of cells. A group of cells having a common origin and performing the same function is called tissue.

          The plant body contains two major types of tissues. They are
1. Meristematic tissue
2. Permanent Tissue

1. Meristematic tissue

             The meristematic cells are rectangular in shape. They are arranged without intercellular space. They are thin walled. They contain prominent nucleus and dense cytoplasm. These are found in the apices of root and shoot. their function is to undergo repeated divisions and leads to growth of the plant.

2. Permanent tissue 

              The tissue which has lost the capacity of cell division is called permanent tissue. It is divided into two types. They are simple tissue and complex tissue. 

Simple tissue 

        Simple tissue is made up of only one type of cell. They are similar in their structure and function. They are classified into three types, namely, 1) parenchyma, 2) collenchyma and 3) sclerenchyma.

1. Parenchyma 

            Parenchyma cells are oval in shape and are thin walled. They are living and are arranged with intercellular spaces. They are present in all the organs of a plant body and their main function is storage.

                When the parenchyma cells contains chloroplasts, They are called chlorenchyma. They perform the function of photosynthesis. In aquatic plants, large intercellular spaces filled with air are called aerenchyma. It gives buoyancy to the plants. 

2. Collenchyma 

           Collenchyma cells are elongated. They have uneven thickening in the corners. The cell wall is made up of cellulose and pectin. These cells are living and are usually seen in the young stem and petiole. They provide support to the young organs

3. Sclerenchyma

            Sclerenchyma cells are polygonal. The cell wall is made up of lignin. These are dead cells, because of the absence of protoplasm. They provide mechanical support and strenght

Complex tissues

          The tissue containing more than one type of cell and performing same function is called complex tissue. They are of two types namely xylem and phloem 

1. Xylem 

         It is a complex tissue. It contains four different types of cells. they are vessels, tracheids, xylem fibres and xylem parenchyma. Its function is to conduct water and minerals from root to shoot 

2. Phloem 

         It is a complex tissue. It contains four different types of cells. They are sieve tubes, companion cells, phloem fibres and phloem parenchyma. Its function is to transport food materials from green parts to the storage regions of the plant.