Explain everything about Permanent tissue with its types, functions and each explanation
Answers
Tissue
A tissue is a cluster of cells, that are alike in configuration and work together to attain a specific function. Different types of plant tissues include permanent and meristematic tissues.
Meristematic tissue:
These tissues have the capability to develop by swift division. They assist in the major growth of the vegetation. Growth in length and growth in diameter of the plant is carried about by these cells. The Meristematic cells are cubical, living cells with a big nucleus. These cells are meticulously crammed with no intercellular spaces. Depending on the section where the meristematic tissues are existing, they are categorized as intercalary, lateral and apical meristems.
- Apical meristem is existent at the growing tips or apical of stems and roots. Apical meristem upsurges the length of the plant.
- Lateral meristem is existent in the radial portion of the stem or root. Lateral meristem upsurges the thickness of the plant.
- Intercalary meristem is found at the internodes or at the base of the leaves. Intercalary meristem upsurges the size of the internode.
Old meristematic cells lose the capability to distribute and convert into permanent tissues. This procedure of capturing up a permanent function, size, and shape is termed as differentiation.
Permanent tissue :
These cells have lost their ability to distribute but are specialised to offer elasticity, flexibility and strength to the plant. These tissues can be additionally categorised into:
- Simple Permanent Tissue: They can be classified into sclerenchyma, collenchyma and parenchyma based on their purpose.
- Complex Permanent Tissue: These tissues include phloem and xylem. Xylem is valuable for the transportation of water and solvable constituents. It is made up of xylem parenchyma, fibres, vessels and tracheids. Phloem is valuable in the transportation of food particles. Phloem consists of phloem parenchyma, phloem fibres, companion cells, sieve cells and sieve tubes.
Parenchyma :
These are alive, polygonal cells with a big central vacuole, and have intercellular spaces amidst them. Parenchymatous cells create ground tissue and pith.
- Parenchyma consisting of chloroplasts are termed as chlorenchyma. The chlorenchyma helps in photosynthesis.
- Parenchyma which consists of big air voids is called aerenchyma. Buoyancy is the main purpose the aerenchyma.
- Some parenchymatous cells perform as storage chambers for starch in vegetable and fruits.
Collenchyma :
These are stretched out, living cells with minute intercellular gaps. Their cell walls are made up of pectin and cellulose. Collenchyma is found in the marginal regions of leaves and stems and offers flexibility with the structural framework and mechanical support to plants.
Sclerenchyma :
These are elongated, dead cells with lignin deposits in their cell wall. They have no intercellular gaps. Sclerenchyma is found in the covering of seeds and nuts, around the vascular tissues in stems and the veins of leaves. Sclerenchyma provides strength to the plant.
Xylem :
It helps in the transport of dissolved substances and water all through the plant. The diverse components of the xylem include vessels, tracheids, xylem fibres and xylem parenchyma. Xylem fibres and Tracheids are made up of lignin, which provides structural support to the plant.
Phloem :
This tissue helps in the transportation of food all through the plant. The diverse elements of phloem include phloem fibres, sieve tubes, phloem parenchyma and companion cells.
Protective tissue :
These provide fortification to the plant. They include the cork and epidermis.
- Epidermis – It is a layer of cell that makes up an outer casing of all the structures in the plant. The stomata perforates the epidermis at certain places. The stomata help in loss of water and gaseous exchange.
- Cork – This is the external protective tissue, which substitutes the epidermal cells in mature stems and roots. Cork cells are lifeless and lack intercellular gaps. Their cell walls are coagulated by suberin, which makes them impervious to gas and Water Molecules.
Permanent Tissue in Plants
In simple words, the permanent tissues in a plant are those tissues that contain nondividing cells. The cells are also modified to perform specific functions in the plants. The cells of the permanent tissue are derived from the meristematic tissue.
The permanent tissue cells are also fully differentiated. The cells are large and a definite shape and size. You can see intercellular spaces being present in between the cells. Large vacuoles are also present inside these cells. The metabolism that occurs in the cells of the permanent tissue is fairly at a lower rate.
The permanent tissue in plants mainly helps in providing support, protection as well as in photosynthesis and conduction of water, minerals, and nutrients. Permanent tissue cells may be living or dead.
Browse more Topics under TissuesIntroduction to TissuesMeristematic TissueEpithelial TissueConnective TissuesMuscular and Nervous TissuesTypes of Permanent Tissues
Permanent tissues can be classified into two types. They are:
Simple permanent tissueComplex Permanent tissue
Simple Permanent Tissues
These tissues are simple. They are made up of only one type of cell. Here, all the cells that make up the tissue are similar and have the same structure, with the same type parts. Simple permanent tissues are again classified into three main types. They are parenchyma, collenchyma, and sclerenchyma.
Parenchyma – The cells of this tissue are living, with thin cell walls. Cells can be oval or round in shape. They have a large central vacuole and a dense cytoplasm. The parenchyma tissue is located in the soft parts of the plant such as cortex and pith. It mainly acts as a packing tissue, providing mechanical support. It also helps in the storage of food. Based on the specific functions, parenchyma can be further classified into Aerenchyma and Chlorenchyma.Collenchyma – These cells are living cells and have an elongated shape. The corners of the cell wall are thickened. There is very little intercellular space present. The collenchyma tissue can be located in the leaf stalks, below the epidermisetc. Its main function is to provide flexibility to the plants as well as mechanical support.Sclerenchyma – The cells of the sclerenchyma tissue are dead. The cell wall is very thick due to the deposition of lignin. The cells of this tissue can be in different shapes and sizes. They are generally located in the leaf veins, hard coverings of the seeds and can also be found surrounding the vascular bundle. The main function of the sclerenchymatic tissue is to provide rigidity and mechanical support to the plant body. They also make the plant stiff and hard.
What are Different Types of Plant Tissues here?
Complex Permanent Tissue
The complex permanent tissues are made up of more than one type of cell. They coordinate together to perform the same specialized functions in the plant body. They are classified into two types – Xylem and Phloem
Xylem – The xylem tissue is responsible for the conduction of water and minerals from the roots to the leaves and stem. It also provides support to the plants. It has four elements. They are tracheids, vessels, xylem parenchyma and xylem fibres.Phloem – This complex permanent tissue helps in the translocation of food that is prepared by photosynthesis in the leaves to various parts of the plant. Phloem consists of four elements. They are sieve tubes, companion cells, phloem fibres and phloem parenchyma.
Q1. What is a permanent tissue? Describe the different types of simple permanent tissue.
Answer: Permanent tissues are a group of living or dead cells which are formed by meristematic tissues that have lost their ability to divide.
That is, these tissues have undergone differentiation and are incapable of meristematic activities.
It is of two types:-
1) Simple permanent tissues 2) Complex permanent tissues
Simple permanent tissues are a group of cells which are similar in origin, structure and function.
They are of three types:-
a) Parenchyma- are unspecialised living cells which have thin cell walls and are loosely packed so that the intercellular spaces are found between cells of this tissue.
Its main function is to support and protect the plants and store food.
b) Collenchyma – are living tissues which also have thin-walled cells but possess thickening of cellulose, water and pectin substances at the corners of the cells.
Its main function is to provide mechanical support, elasticity, and tensile strength to the plants.
c) Sclerenchyma- are tissues consists of thick-walled and dead cells.
The cells have hard and thick