Table of Contents

Permanent Tissues in Plants & their Types

This article we will discuss about Permanent Tissues in Plants

These cells are derived from meristematic tissues
They lost the power of cell division
Cells of permanent tissue are matured, definite shape, size and function
The permanent tissues are broadly classified as 2 types:- simple permanent tissue and
complex permanent tissue

Simple permanent tissue

Simple permanent tissue consists of group of uniform cells which are similar in structure and carry out same function
Simple permanent tissues are three types: parenchyma, collenchyma and sclerenchyma

Parenchyma

Parenchyma is the commonest simple tissue
First differentiated tissue & precursor of other tissue
It is very primitive type of tissue and also called fundamental tissue
Parenchyma are living and arranged loosely with intercellular spaces
Cells are compactly packed or they have intercellular spaces between them
Parenchyma consist of oval, round, polygonal, elongated or irregular cells
Parenchyma cells are thin walled. Cell wall is made up of pectocellulose
It is most abundant tissue, found in:- cortex, pith and leaf mesophyll

Collenchyma

Collenchyma are living mechanical tissue
The shape of collenchyma cell can be variable. It may be oval, spherical, round or polygonal
Cell wall contains cellulose, hemicelluloses and pectic materials
Cellulose, hemicellulose and pectin are deposited at the corners of cell
Found in under the epidermis of young stems, leaf veins, leaf margins and petiole
Collenchyma is absent in mature plant parts, roots and monocots
Intercellular spaces are absent and cells are compactly arranged

Sclerenchyma

Sclerenchyma are dead mechanical tissues occurring in mature organs of plant body
Cells of sclerenchyma are long, narrow, thick walled, lignified without protoplasts
Pits are also found. It may be simple pits or bordered pits
Found in cortex, pericycle, xylem and phloem region
Main function is provides mechanical support to plant organs
Based on size and shape sclerenchyma cells are of two types:- Sclerenchyma fibres and Sclereids

Complex permanent tissue

Complex tissues are made of more than one type of cells and they are heterogenous
They are also known as vascular tissue or conducting tissue
Complex tissues are absent in gametophytes
Complex tissues are of two types:- Xylem and Phloem

Xylem

The term xylem was introduced by nageli (1858)
Xylem is conducting tissue which conducts water and mineral nutrients upwards from the root to the leaves
Xylem besides conduction also provide mechanical strength
They are composed of four different types of cells
The elements of xylem are xylem tracheids, xylem vessels, xylem fibres and xylem parenchyma

Phloem

The term phloem was introduced by nageli
Phloem is conducting tissue which conducts food materials from the leaves to other parts of the plants
First formed phloem is protophloem and later formed phloem is called metaphloem
They are composed of four different types elements
The elements of Phloem are sieve elements, companion cells, phloem fibres and phloem parenchyma

For more detailed information about plant anatomy, download now full study material as PDF