Chapter 6 Tissue - Class 9 PDF Download

 Page 1


Chapter 6 Tissues 
Tissue – A group of cells that have similar structure and perform a specific function. 
Plant Tissues 
1. Meristematic tissue 
? It consists of cells that are continuously dividing. 
? It helps in the growth of the plant and is found in the growing regions of the plant such as the 
root tip and the shoot tip. 
? The cells of meristematic have a dense cytoplasm because it is rich in food material for the 
dividing cells. 
? The food is not stored but utilized during division so they do not even have vacuoles. 
Meristematic tissue is further classified into three categories –  
a. Apical meristem – Found on the apical regions of the plant such as the root tips and the shot tip. 
It increases the height of the plant. 
b. Lateral meristem or cambium – it increases the girth or diameter of a plant. 
It is present inside the stem of the plant between xylem and phloem (later in the chapter). 
c. Intercalary meristem – It is present between the nodes of the plant or at the base of the leaves. 
It increases the height of the nodal region. 
 
          Fig. Meristematic tissue in plants 
 
Permanent tissue 
Differentiation – the process of taking up a permanent shape, size and function by a cell is called 
differentiation. 
Permanent tissues are formed once the cells have been differentiated. 
 
1. Simple Permanent Tissue  
Made up of only one type of cells. 
 Types of simple permanent tissues: 
a. Parenchyma tissues  
? Contains living cells 
? Packaging tissue to fill up spaces. 
? Unspecialized cells 
Apical Meristem 
Lateral meristem 
Intercalary meristem 
Page 2


Chapter 6 Tissues 
Tissue – A group of cells that have similar structure and perform a specific function. 
Plant Tissues 
1. Meristematic tissue 
? It consists of cells that are continuously dividing. 
? It helps in the growth of the plant and is found in the growing regions of the plant such as the 
root tip and the shoot tip. 
? The cells of meristematic have a dense cytoplasm because it is rich in food material for the 
dividing cells. 
? The food is not stored but utilized during division so they do not even have vacuoles. 
Meristematic tissue is further classified into three categories –  
a. Apical meristem – Found on the apical regions of the plant such as the root tips and the shot tip. 
It increases the height of the plant. 
b. Lateral meristem or cambium – it increases the girth or diameter of a plant. 
It is present inside the stem of the plant between xylem and phloem (later in the chapter). 
c. Intercalary meristem – It is present between the nodes of the plant or at the base of the leaves. 
It increases the height of the nodal region. 
 
          Fig. Meristematic tissue in plants 
 
Permanent tissue 
Differentiation – the process of taking up a permanent shape, size and function by a cell is called 
differentiation. 
Permanent tissues are formed once the cells have been differentiated. 
 
1. Simple Permanent Tissue  
Made up of only one type of cells. 
 Types of simple permanent tissues: 
a. Parenchyma tissues  
? Contains living cells 
? Packaging tissue to fill up spaces. 
? Unspecialized cells 
Apical Meristem 
Lateral meristem 
Intercalary meristem 
? Thin cell walls 
? Loosely packed and have large spaces between them. 
? Provide support and stores food. 
? Chlorenchyma – Parenchyma tissue that contain chlorophyll and performs 
photosynthesis. 
? Aerenchyma – Parenchyma tissue that contain large air spaces and provide buoyancy 
(floating ability) to plants.  
Fig. Parenchyma tissue in longitudinal section 
 
   Fig. Transverse section   Fig. Longitudinal section 
 
b. Collenchyma 
? Contains living cells 
? Provides flexibility to the plants 
? Present in leaf and stem. 
? Provides mechanical strength to the plant. 
Fig. Parenchyma tissue in transverse section 
Page 3


Chapter 6 Tissues 
Tissue – A group of cells that have similar structure and perform a specific function. 
Plant Tissues 
1. Meristematic tissue 
? It consists of cells that are continuously dividing. 
? It helps in the growth of the plant and is found in the growing regions of the plant such as the 
root tip and the shoot tip. 
? The cells of meristematic have a dense cytoplasm because it is rich in food material for the 
dividing cells. 
? The food is not stored but utilized during division so they do not even have vacuoles. 
Meristematic tissue is further classified into three categories –  
a. Apical meristem – Found on the apical regions of the plant such as the root tips and the shot tip. 
It increases the height of the plant. 
b. Lateral meristem or cambium – it increases the girth or diameter of a plant. 
It is present inside the stem of the plant between xylem and phloem (later in the chapter). 
c. Intercalary meristem – It is present between the nodes of the plant or at the base of the leaves. 
It increases the height of the nodal region. 
 
          Fig. Meristematic tissue in plants 
 
Permanent tissue 
Differentiation – the process of taking up a permanent shape, size and function by a cell is called 
differentiation. 
Permanent tissues are formed once the cells have been differentiated. 
 
1. Simple Permanent Tissue  
Made up of only one type of cells. 
 Types of simple permanent tissues: 
a. Parenchyma tissues  
? Contains living cells 
? Packaging tissue to fill up spaces. 
? Unspecialized cells 
Apical Meristem 
Lateral meristem 
Intercalary meristem 
? Thin cell walls 
? Loosely packed and have large spaces between them. 
? Provide support and stores food. 
? Chlorenchyma – Parenchyma tissue that contain chlorophyll and performs 
photosynthesis. 
? Aerenchyma – Parenchyma tissue that contain large air spaces and provide buoyancy 
(floating ability) to plants.  
Fig. Parenchyma tissue in longitudinal section 
 
   Fig. Transverse section   Fig. Longitudinal section 
 
b. Collenchyma 
? Contains living cells 
? Provides flexibility to the plants 
? Present in leaf and stem. 
? Provides mechanical strength to the plant. 
Fig. Parenchyma tissue in transverse section 
? Cells are irregularly thickened at corners. 
? Cells have very little intercellular spaces. 
 
 
 
c. Sclerenchyma  
? It makes the plant hard and tough 
? The cells in this tissue are dead 
? The cell walls are thickened with lignin 
? Lignin is a chemical that hardens the cell walls 
? There are no intercellular spaces 
? It is present in stems around vascular bundles (later in the chapter), seeds and nuts. 
? Provides strength to the plants. 
Fig. Sclerenchyma tissue – Transverse section Longitudinal section 
 
d. Epidermis 
? Outermost layer of cells in a plant. 
Fig. Collenchyma tissue in transverse section 
Fig. Collenchyma tissue in longitudinal section 
Page 4


Chapter 6 Tissues 
Tissue – A group of cells that have similar structure and perform a specific function. 
Plant Tissues 
1. Meristematic tissue 
? It consists of cells that are continuously dividing. 
? It helps in the growth of the plant and is found in the growing regions of the plant such as the 
root tip and the shoot tip. 
? The cells of meristematic have a dense cytoplasm because it is rich in food material for the 
dividing cells. 
? The food is not stored but utilized during division so they do not even have vacuoles. 
Meristematic tissue is further classified into three categories –  
a. Apical meristem – Found on the apical regions of the plant such as the root tips and the shot tip. 
It increases the height of the plant. 
b. Lateral meristem or cambium – it increases the girth or diameter of a plant. 
It is present inside the stem of the plant between xylem and phloem (later in the chapter). 
c. Intercalary meristem – It is present between the nodes of the plant or at the base of the leaves. 
It increases the height of the nodal region. 
 
          Fig. Meristematic tissue in plants 
 
Permanent tissue 
Differentiation – the process of taking up a permanent shape, size and function by a cell is called 
differentiation. 
Permanent tissues are formed once the cells have been differentiated. 
 
1. Simple Permanent Tissue  
Made up of only one type of cells. 
 Types of simple permanent tissues: 
a. Parenchyma tissues  
? Contains living cells 
? Packaging tissue to fill up spaces. 
? Unspecialized cells 
Apical Meristem 
Lateral meristem 
Intercalary meristem 
? Thin cell walls 
? Loosely packed and have large spaces between them. 
? Provide support and stores food. 
? Chlorenchyma – Parenchyma tissue that contain chlorophyll and performs 
photosynthesis. 
? Aerenchyma – Parenchyma tissue that contain large air spaces and provide buoyancy 
(floating ability) to plants.  
Fig. Parenchyma tissue in longitudinal section 
 
   Fig. Transverse section   Fig. Longitudinal section 
 
b. Collenchyma 
? Contains living cells 
? Provides flexibility to the plants 
? Present in leaf and stem. 
? Provides mechanical strength to the plant. 
Fig. Parenchyma tissue in transverse section 
? Cells are irregularly thickened at corners. 
? Cells have very little intercellular spaces. 
 
 
 
c. Sclerenchyma  
? It makes the plant hard and tough 
? The cells in this tissue are dead 
? The cell walls are thickened with lignin 
? Lignin is a chemical that hardens the cell walls 
? There are no intercellular spaces 
? It is present in stems around vascular bundles (later in the chapter), seeds and nuts. 
? Provides strength to the plants. 
Fig. Sclerenchyma tissue – Transverse section Longitudinal section 
 
d. Epidermis 
? Outermost layer of cells in a plant. 
Fig. Collenchyma tissue in transverse section 
Fig. Collenchyma tissue in longitudinal section 
? It protects the internal parts of the cell 
? Waxy and water resistant in the aerial parts of the plant. 
? There are no intercellular spaces to prevent water loss. 
? Although small pores called stomata are present in the epidermis of the leaves that 
help in exchange of gases and transpiration (loss of water). 
? Epidermis in roots have root hair, which increases the surface area to absorb water 
and minerals from the soil. 
? In desert pants it has a thick layer of cutin (waterproof chemical substance) to prevent 
water loss. 
? As it grows older it is replaced by several layer of secondary meristem called cork or 
bark, which consist of dead cells arranged without intercellular spaces. 
? A chemical substance called suberin in found in the walls of cork cells, which make it 
impervious to water and gases. 
   
 
 
 
 
 
                                       Fig. Surface view of a leaf 
 
2. Complex permanent Tissue 
It is composed of two or more type of cells 
Examples of Complex permanent tissues 
a. Xylem 
b. Phloem 
They are conducting or transporting tissues.  
 
Structure of xylem 
? Different types of cells present in xylem are tracheid, vessels, xylem parenchyma and 
xylem fibers. 
? All the cells except xylem parenchyma are dead at maturity. 
? The cells have thick cell walls. 
? Tracheid and vessels are tubular structure and helps in transportation of water and 
minerals vertically. 
? Xylem parenchyma stores food and helps in sideways conduction of water and minerals. 
? Xylem fibers play supportive role in conduction. 
? Xylem transports water and minerals from the roots to the leaves. Xylem can transport 
only in one direction. 
 
 
Guard cells 
Stomatal pore 
Page 5


Chapter 6 Tissues 
Tissue – A group of cells that have similar structure and perform a specific function. 
Plant Tissues 
1. Meristematic tissue 
? It consists of cells that are continuously dividing. 
? It helps in the growth of the plant and is found in the growing regions of the plant such as the 
root tip and the shoot tip. 
? The cells of meristematic have a dense cytoplasm because it is rich in food material for the 
dividing cells. 
? The food is not stored but utilized during division so they do not even have vacuoles. 
Meristematic tissue is further classified into three categories –  
a. Apical meristem – Found on the apical regions of the plant such as the root tips and the shot tip. 
It increases the height of the plant. 
b. Lateral meristem or cambium – it increases the girth or diameter of a plant. 
It is present inside the stem of the plant between xylem and phloem (later in the chapter). 
c. Intercalary meristem – It is present between the nodes of the plant or at the base of the leaves. 
It increases the height of the nodal region. 
 
          Fig. Meristematic tissue in plants 
 
Permanent tissue 
Differentiation – the process of taking up a permanent shape, size and function by a cell is called 
differentiation. 
Permanent tissues are formed once the cells have been differentiated. 
 
1. Simple Permanent Tissue  
Made up of only one type of cells. 
 Types of simple permanent tissues: 
a. Parenchyma tissues  
? Contains living cells 
? Packaging tissue to fill up spaces. 
? Unspecialized cells 
Apical Meristem 
Lateral meristem 
Intercalary meristem 
? Thin cell walls 
? Loosely packed and have large spaces between them. 
? Provide support and stores food. 
? Chlorenchyma – Parenchyma tissue that contain chlorophyll and performs 
photosynthesis. 
? Aerenchyma – Parenchyma tissue that contain large air spaces and provide buoyancy 
(floating ability) to plants.  
Fig. Parenchyma tissue in longitudinal section 
 
   Fig. Transverse section   Fig. Longitudinal section 
 
b. Collenchyma 
? Contains living cells 
? Provides flexibility to the plants 
? Present in leaf and stem. 
? Provides mechanical strength to the plant. 
Fig. Parenchyma tissue in transverse section 
? Cells are irregularly thickened at corners. 
? Cells have very little intercellular spaces. 
 
 
 
c. Sclerenchyma  
? It makes the plant hard and tough 
? The cells in this tissue are dead 
? The cell walls are thickened with lignin 
? Lignin is a chemical that hardens the cell walls 
? There are no intercellular spaces 
? It is present in stems around vascular bundles (later in the chapter), seeds and nuts. 
? Provides strength to the plants. 
Fig. Sclerenchyma tissue – Transverse section Longitudinal section 
 
d. Epidermis 
? Outermost layer of cells in a plant. 
Fig. Collenchyma tissue in transverse section 
Fig. Collenchyma tissue in longitudinal section 
? It protects the internal parts of the cell 
? Waxy and water resistant in the aerial parts of the plant. 
? There are no intercellular spaces to prevent water loss. 
? Although small pores called stomata are present in the epidermis of the leaves that 
help in exchange of gases and transpiration (loss of water). 
? Epidermis in roots have root hair, which increases the surface area to absorb water 
and minerals from the soil. 
? In desert pants it has a thick layer of cutin (waterproof chemical substance) to prevent 
water loss. 
? As it grows older it is replaced by several layer of secondary meristem called cork or 
bark, which consist of dead cells arranged without intercellular spaces. 
? A chemical substance called suberin in found in the walls of cork cells, which make it 
impervious to water and gases. 
   
 
 
 
 
 
                                       Fig. Surface view of a leaf 
 
2. Complex permanent Tissue 
It is composed of two or more type of cells 
Examples of Complex permanent tissues 
a. Xylem 
b. Phloem 
They are conducting or transporting tissues.  
 
Structure of xylem 
? Different types of cells present in xylem are tracheid, vessels, xylem parenchyma and 
xylem fibers. 
? All the cells except xylem parenchyma are dead at maturity. 
? The cells have thick cell walls. 
? Tracheid and vessels are tubular structure and helps in transportation of water and 
minerals vertically. 
? Xylem parenchyma stores food and helps in sideways conduction of water and minerals. 
? Xylem fibers play supportive role in conduction. 
? Xylem transports water and minerals from the roots to the leaves. Xylem can transport 
only in one direction. 
 
 
Guard cells 
Stomatal pore 
 Fig. Tracheid   Vessel  Xylem parenchyma 
 
Structure of Phloem 
? Different types of cells present in phloem are sieve tube, companion cells, phloem fibers 
and phloem parenchyma cells. 
? Sieve tube are tubular structures with punctured walls that help in transportation of 
prepared food from the leaves to various parts of the body. 
? All the cells except phloem fibers are living 
? Phloem transports prepared food from leaves to all the other parts of the plant. Phloem ca 
transport bi-directionally  
       Fig. Phloem tissue 
 
Animal Tissues 
1. Epithelial Tissue 
? Protective innermost and outermost layer of cells present on various organs. 
? E.g. Skin, the linings of mouth, blood vessels and lungs. 
? Cells are tightly packed with no intercellular spaces to form a continuous sheet. 
? Permeability (ability to allow entry or exit through itself) varies and play an important role to 
regulate exchange of materials. 
Types of epithelial tissue: 
a. Squamous epithelial  
? Extremely thin and consist of simple flat epithelial cells.