Page 1 - Lesson Notes

SAI International School
Subject- Biology, Class- IX
Chapter- Tissues
Subtopic- Simple Permanent Tissue
Module- 10

Lesson Notes

Introduction

 Cell is the basic structural and functional unit of all organisms.
 A group of cells similar in structure that work together to perform a particular

function forms a tissue.

 All types of tissues have two basic components:
(a)Cells: having common origin and function.

(b)Intercellular substances: Are non-living, fibrous, jelly-like substances.
Importance of tissues:

 In unicellular organism (Amoeba) single cell performs all basic functions,
whereas in multi-cellular organisms (Plants and Animals) shows division of

labour as Plant tissue & Animal tissues.

Formation of tissues has brought about divisionof labour in multicellular
organisms.

 Tissues become organized to form organs and organs into organ systems.

 Workload of individual cell ahs decreased due to origin of tissues.
 As a result of improved organization and higher efficiency, multicellular

organisms have higher survival.

Classification of tissues:
 Tissues are broadly classified as

(a) Plant tissues.
(b) Animal tissues

Comparison between Plant and Animal tissues