9th Class Science Notes in English chapter 6 Tissue.
📚 Chapter - 6 📚
🔹 TISSUE 🔹
🔹Plant tissues are of various types and they are made up of similar types of cells. They are different from animal tissues since there are several differences between the animal and plant cell.
🔹 (1) Meristematic Tissues
🔹 (2) Permanent Tissues
✳️ (2) Permanent Tissue :- The tissues that are completely grown and have lost the ability of division are known as permanent tissues. The meristematic tissues divide and differentiate to form the permanent tissues.
👉 Permanent Tissues are of two types:-
🔹(i) Simple Tissues
🔹(ii) Complex Tissues
Consist of only one type of cells.
👉 Types of Simple Permanent Tissues:
Composed of unspecialised living cells with relatively thin cell walls, intercellular space, present in soft parts of the plant. Their main function is storage.
Composed of living and elongated cells with cell walls irregularly thickened at the comers. No intercellular space. It provides mechanical support and elasticity to plant. It helps in bending of leaves and stems.
🔹Sclerenchyma:- Composed of long, narrow, and thick-walled cells. This tissue is made up of dead cells and there are no intercellular spaces. Sclerenchyma cells are dead, present in seeds, nuts, the husk of a coconut, fibres of jute etc.
🔹Epidermis Simple Tissues:- Epidermis tissue covers the entire body of plant. They protect plant from injury, germs and water loss.
🔹Cork Simple Tissues:- These types of tissue consist dead cells with no intercellular spaces. They form the outer layer of old tree trunks.