plant anatomy is the study of the internal structures of a plant and finds out how they function or work.
Tissue.
A group of the same type of cell with the common origin which carries out a particular function is known as the tissues.
The tissue is of two types.
- Meristematic tissue
- permanent tissue.
1. Meristematic tissue.
It has the ability of division they are round enclosed in shape they have a thin wall and polygonal in shape large Protoplasm. They have a large nucleus.
Types of meristematic tissue on the basis of their position.
According to the position of meristematic tissue. There are three types of meristematic tissues
- Apical Meristem.
- Intercalary Meristem.
- Lateral Meristem.
Apical Meristem.
These Meristematic tissues are present of the growing region of the plant the apex of the root and the give rise to primary and permanent tissue and increase the length of the plant.
Intercalary Meristem
These are the separate tissue of apical Meristem these are separated from during growth and present in the between the cell of permanent tissue.
They also increase the length of the plant body they are short-lived tissue disappear or Soon convert into permanent tissue.
Lateral Meristem
These tissues are present in a vascular bundle in between xylem and phloem this tissue produce secondary growth the increase the diameter of the plant.
Permanent tissues.
These are the tissue which has less power of division they may be living or dead they may be thinly walled and thick-walled.
Type of permanent tissues.
There are three types of permanent tissue.
simple tissue
Complex tissue
secondary tissue.
Simple tissue.
Simple tissue consists of one type of cells having no power of division there are three types of simple tissues
Parenchyma.
collenchyma.
Sclerenchyma.
Parenchyma.
Parenchyma consists of characteristics isodiametric cell they are thin-walled spiracle or rounded or oval in shape.
The cell wall is thin and made up of cellulose.
They are usually living and having nucleus they have large intercellular space.
They are found in the soft part of the plant like pith and cortex.
Parenchyma tissue provides support to plant and parenchyma found in root and stem.
When it stores food called storage Chyna when it contains chloroplast having chlorophyll and perform photosynthesis called chlorenchyma. In aquatic plants, parenchyma has large air spaces which help to float on the water found in the oft part of the plant.
Collenchyma
Collenchyma consists of an elongated cell and became circular in transverse section.
The cell wall is thick with simple pits
The cells are living elongated irregular thick at the corner made up of cellulose and pectin.
They have less intracellular spaces they are found in hard parts of the plant like hypodermis.
They perform both mechanical support and vital functions found in leaf stalk below the epidermis of leaf and stem.
Sclerenchyma.
The cell of sclerenchyma is double-walled hard and dead elongated in shape they have strongly lignified walls and have pits.
The lack of intercellular spaces they are dead tissues the wall substance usually show concentric.
They perform the mechanical function the cells provide rigidity and strength to plant and make it hard and can bear stress and strain.
They are found in stem around the vascular bundle in on the veins of the leaf.
Sclerenchyma may be as follow
fibres and stone cells or sclerotic.
Fibres.
These are along with narrow fibre like those cells.
They are pointed at them both and they have lignified walls with simple pits.
They vary much in length and shape.
They are present in the vascular bundles they are over letting and meshwork.
Stone Cells or sclerotic.
The cells are more or less oval in and spherical in shape.
The walls are very thick and strongly lignified.
They occur in cortex hard Court of seeds nut and stone fruits.
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