Plant Tissue
A group of specialized cells to perform specific functions in plants are plant tissues. They show the characteristics of growth in specific regions as they are located in those points.
They can be further classified into; Meristematic (dividing) Tissues and Permanent (Non-dividing, specific) Tissues.
Meristematic Tissues
The types of plant tissues in which the cells can divide continuously to enable the plant to grow and increase in length are called meristematic tissues. These types of tissues are found in the growing regions of the plant. They show the following characteristics;
Types: Based on their location these tissues can be categorized into; Apical Meristem, Intercalary Meristem, and Lateral Meristem.
|
Types of Meristem |
Location |
Functions |
Diagram |
|---|---|---|---|
|
Apical Meristem |
At the growing tips of stem, root, and axillary buds. |
Elongation of root and stem to show primary growth. |
|
|
Intercalary Meristem |
At the stem internodes, and leaf bases. |
Forms new cells continuously, and increases the length of a part. |
|
|
Lateral Meristem |
At the lateral sides of the root, stem, and longitudinally below the bark. |
Increases the girth of the plant’s body and parts. |
Permanent Tissues
The types of plant tissues which have lost their ability to divide and have attained permanent shape, size, and function are called permanent tissues.
They are classified further into; Simple Permanent Tissues, Complex Permanent Tissues, and Protective Tissues.
Simple Permanent Tissues
These permanent tissues are made up of only one type of cells that are similar in structure and function. They are further classified into; Parenchyma, Sclerenchyma, and Collenchyma.
|
Types |
Location |
Characteristics |
Functions |
|---|---|---|---|
|
Parenchyma |
Found in the soft parts of the stem, leaves, and roots. |
The most common type of living cells are loosely arranged, thin cell walls, and have round or isodiametric shapes. |
Stores food, fill spaces, helps in cell-to-cell transport, stores wastes, and maintains the shape and firmness of the body. |
|
Sclerenchyma |
Found in the stems around the vascular bundle, veins of leaves, and hard covering of seeds and nuts |
They are dead cells with pointy tapered ends, closely packed, and have thickened cell walls by lignin. |
It gives strength, rigidity, flexibility, and elasticity to the plant body. |
|
Collenchyma |
Found below the epidermis of the dicot stem, veins of leaves, and in non-woody plants. |
Consists of living cells, lacks intercellular spaces, cells are elongated, and have irregularly thick cell walls at the corner. |
It provides mechanical support, and elasticity to young plants. |
Complex Permanent Tissues
Permanent tissues that are made up of more than one type of cells that coordinates to perform common functions like the transport of water, minerals, and food throughout the body. They are further classified into; Xylem, and Phloem.
|
Types |
Location |
Characteristics |
Function |
|---|---|---|---|
|
Xylem |
Found in the stem, roots, and leaves |
Consists of tracheid, xylem vessels, xylem fibers, and xylem parenchyma. |
Dead tubular tracheid and xylem vessels help in the transport of water from root to shoot. Living xylem parenchyma stores food and dead xylem fibers supports the plant body. |
|
Phloem |
Found beneath the bark of the plant. |
Consists of sieve cells, sieve tubes, companion cells, phloem parenchyma, and phloem fibers. |
Living sieve cells and sieve tubes help in the translocation of food throughout the plant’s body. Living companion cells regulates the function of sieve tubes. Living phloem parenchyma stores food and transports food to the non-green part of the plant. Dead phloem fibers provide mechanical support. |
Protective Tissues: These permanent tissues protect the plant’s body from any external or internal injury. They are further classified into; Epidermis, and Cork.
|
Types |
Location |
Characteristics |
Function |
|---|---|---|---|
|
Epidermis |
Covers the whole outermost layer of the plant’s body. |
They have cells that are elongated and flattened with no intercellular spaces between them. |
Protects from loss of water and infectious agents. |
|
Cork |
Found in the outer bark of woody plants, particularly in trees. |
They have cells that are dead, water-resistant, and durable. Also consists of a waxy substance called Suberin that makes the tissue impervious to water and gases |
Protects from desiccation, infection, and mechanical injury. |
Tissues Class 9 Notes CBSE Science Chapter 6
Tissues are a group of specialized cells that possesses similar structure, have a similar origin, and are responsible for performing similar type of functions. In unicellular organisms, the cell is responsible for performing all the vital functions whereas in multicellular organisms different groups of cells are assigned different functions based on the information present in the DNA. These specialized groups of cells are called tissues.
In Chapter 6 Tissue, you will learn the following content:
Table of Content
- Introduction to Tissue
- Difference between Plant and Animal Tissue
- Plant Tissue
- Animal Tissue