Meristematic Tissue: Function, Characteristics, Types & Examples

Ans: Apical meristem is capable of division and growth in the root and shoots tips in plants. The actual apical meristem is a cluster of densely packed and undifferentiated cells. From these cells will come all of the various cell structures the plant uses.

Ques: Define the term 'meristem'? (2 Marks)

Ans: Meristematic tissue is a type of tissue that is usually found in the plant and has the capacity for the division of plants. They continue to divide till the te of differentiation and play a crucial role in the growth of the plant and having a proper structure. And the zones present in meristematic tissues are known as meristems.

Ans: The following three are the important characteristics of a meristematic tissue:-

• The wall of meristematic tissue is very thin. 
• Only one nucleus is present inside the cell of a meristematic tissue which is very big in size.
• The meristematic tissue provides relief to plants in case of injuries to the plants.
• A dense protoplasm is available in the cell of the meristematic tissue.
• It possesses a quality of self-renewal.
• It implies that whenever a cell is divided, one cell will be similar to the parent cell.
• Another cell present will be forming a specialized structure of a plant.
• The metabolic activity in the cells of the meristematic tissues is very high.

Ans: The primary function of meristematic tissue is the division of cells, and the cell walls are so thin that it requires a dense cytoplasm to perform their function, and due to this there is a lack of vacuoles present in the meristematic tissues.

Ans:  Differences between meristematic and permanent tissues are as follows: 

Ans: Tissue is defined as a group of cells that possess a similar structure and perform a specific function. The word tissue comes from a French verb that means to “weave”.

• Plant tissue is a collection of similar cells that perform and organize functions for the plant.
• Each plant tissue is specialized for a unique purpose and combined with other tissues of plants to create organs such as flowers, leaves, stems, and roots.

Ans: Meristematic tissues on the basis of function are as follows:- 

• Protoderm: It helps in the formation of the epidermis and is the outermost plant tissue and protects the plants from any type of mechanical shock.
• Procambium: It aids in giving rise to xylem and phloem in a plant cell and is the innermost tissue and provides water and required nutrients to various parts of the plants.
• Ground Meristem: The cells present ate very large and have a thick wall which helps in the formation of the cortex, pith, and pericycle.

Ans: The origin of meristematic tissues are:-

• Promeritism: it is the earliest and the youngest meristematic tissue. It has the tendency to originate from the embryo of the plant. Promeritism is the birthplace of primary meritism and is mainly found in the root and shoot tips.
• Primary Meritism: It originates from the promeritism and helps the cell to divide and aids in forming a permanent tissue.
• Secondary Meritism: Primary meristem is responsible for the origination of secondary meristem and secondary meristem is mainly responsible for the production of permanent tissue.

Ans: The position of meristematic tissues are:-

• Apical Meristem: They are mainly found in the roots and shoots of the plant and assist the plant to grow and help in cellular enlargement. It is divided into the promeritism zone and the meristematic zone.
• Intercalary Meristem:- It is mainly found in grasses, leaves, monocots, and pines and plays a crucial role in increasing the length of the internode and is a part of the apical meristem.
• Lateral Meristem:- It is mainly responsible for increasing the thickness of the plant and is located on stems and roots on the lateral side and gives rise to the secondary permanent tissues. The two types of lateral meristem are vascular cambium and cork cambium.

Ans:

• Meristematic tissue helps in the active division of the plant tissue.
• It helps in the creation of the new organ of the plant.
• It provides support to the development of the new organs of the plant.
• Meristematic tissue provides support to the secondary organ of the plants.
• It helps in the growth of the plants if root development is interrupted.

Ans: The hormone responsible present in the meristematic tissue are as follows:

• Auxin: Auxin is a naturally occurring plant hormone that is responsible for the production of the apical meristematic tissue. It plays an important role in a plant's growth and behavioural cycle. These types of hormones exhibit morphogen-like characteristics.
• Cytokinin: Cytokinin is another hormone found in the plant body that acts as a messenger to the cells of the plants. It helps in the proliferation of the cell and helps in the growth of the meristematic tissue.

Ans: Korper-Kappe theory states that theroot apex are organised in the form of plane of division. In this roots are divided into two planes namely the transverse division and longitudinal division. 

• The sequence of different cells of root apex are called T Division.
• Since walls of the cell form the configuration in the shape of T.
• The concept was introduced by Schuepp in 1917.
• It is similat to tunica-corpus concept of shoot apex of plants.