Structural Organisation in Animals PPT Biology Class 11

 Page 1


STRUCTURAL ORGANISATION 
IN ANIMALS
Page 2


STRUCTURAL ORGANISATION 
IN ANIMALS
7.1 ANIMAL TISSUES
- In unicellular organisms, all functions 
(digestion, respiration & reproduction) 
are performed by a single cell. 
- In the complex body of multicellular 
animals the same basic functions are 
carried out by different groups of cells 
in a well organised manner. 
Page 3


STRUCTURAL ORGANISATION 
IN ANIMALS
7.1 ANIMAL TISSUES
- In unicellular organisms, all functions 
(digestion, respiration & reproduction) 
are performed by a single cell. 
- In the complex body of multicellular 
animals the same basic functions are 
carried out by different groups of cells 
in a well organised manner. 
? The body of a simple organism (Hydra) is 
made of different types of cells and the 
number of cells in each type can be in 
thousands. 
? The human body is composed of billions 
of cells to perform various functions. 
? In multicellular animals, a group of similar 
cells along with intercellular substances 
perform a specific function. Such an 
organisation is called tissue.
Page 4


STRUCTURAL ORGANISATION 
IN ANIMALS
7.1 ANIMAL TISSUES
- In unicellular organisms, all functions 
(digestion, respiration & reproduction) 
are performed by a single cell. 
- In the complex body of multicellular 
animals the same basic functions are 
carried out by different groups of cells 
in a well organised manner. 
? The body of a simple organism (Hydra) is 
made of different types of cells and the 
number of cells in each type can be in 
thousands. 
? The human body is composed of billions 
of cells to perform various functions. 
? In multicellular animals, a group of similar 
cells along with intercellular substances 
perform a specific function. Such an 
organisation is called tissue.
? Cells, tissues, organs and organ
systems split up the work in a way
that ensures the survival of the body
as a whole and exhibit division of
labour.
? A tissue is defined as group of cells
along with intercellular substances
performing one or more functions in
the body.
Page 5


STRUCTURAL ORGANISATION 
IN ANIMALS
7.1 ANIMAL TISSUES
- In unicellular organisms, all functions 
(digestion, respiration & reproduction) 
are performed by a single cell. 
- In the complex body of multicellular 
animals the same basic functions are 
carried out by different groups of cells 
in a well organised manner. 
? The body of a simple organism (Hydra) is 
made of different types of cells and the 
number of cells in each type can be in 
thousands. 
? The human body is composed of billions 
of cells to perform various functions. 
? In multicellular animals, a group of similar 
cells along with intercellular substances 
perform a specific function. Such an 
organisation is called tissue.
? Cells, tissues, organs and organ
systems split up the work in a way
that ensures the survival of the body
as a whole and exhibit division of
labour.
? A tissue is defined as group of cells
along with intercellular substances
performing one or more functions in
the body.
7.1 ANIMAL TISSUES
- Structure of the cells varies 
according to their function. 
- So, tissues are different and 
are broadly classified into 
four types: 
(i) Epithelial, 
(ii) Connective, 
(iii) Muscular and 
(iv) Neural.