NCERT 9TH CLASS SCIENCE CHAPTER TISSUE
- In unicellular organisms a single cell performs all the vital
- activities for example, digestion, respiration, excretion
- In case of multicellular organisms specialized functions are performed by a different groups of cells
- possessing a well-developed division of labour to provide highest possible efficiency of particular function.
- As blood flows for transportation of O2, CO2, food, hormones & waste material, muscle cells are involved
- in movement etc so cells make a group called tissue.
- A tissue is defined as a group of cells with similar structure, organized to do a common function.
- Term tissue was coined by Bichat.
- Branch of biology which deals with the study of tissue is called Histology.
- In plants and animals tissues are found but these tissues have differences on various aspects which are following.
Plant tissues are of two types on the basis of their dividing capacity :-
1. Meristematic tissue (growing tissue)
2. Permanent tissue
1. MERISTEMATIC TISSUE
- These are living ti