Animal Tissues

Synopsis

Levels of Organisation

• Cell: The basic structural and functional unit of a living organism is called a cell. Examples: Nerve cell, muscle cell 
• Tissue: A group of cells with a common origin and similar structure and function being held together by a cementing substance forms a tissue.
  Examples: Connective tissue, meristematic tissue 
• Organ: Different types of tissues working together and contributing to some specific function of the body constitute an organ.
  Examples: Stomach, heart 
• Organ system: Different organs coordinate to perform a specific life process and form an organ system.
  Examples: Digestive system, nervous system 
• Organism: Various organ systems working simultaneously together constitute an organism.
  Examples: Plant, animal
  

Importance of Tissues

• Formation of tissues ensures division of labour in multicellular organisms.
• Tissues organise to form organs and organs form organ systems.
• The workload of individual cells decreases due to the origin of tissues.
• Improved organisation and higher efficiency ensure greater survival of multicellular organisms.

Differences between Plant and Animal Tissues

 

• Epithelial tissue forms the protective tissue in animals.
  
  
  
  

Types of Epithelial Tissue

 

 

Connective Tissue

• Connective tissue is a type of animal tissue that connects organs of the body.
  

Types of Connective Tissue

A. Connective Tissue Proper/Loose Connective Tissue

• It is composed of irregular cells scattered and embedded in a soft matrix and encompasses all internal organs and body cavities.
• It acts as a binding and supporting structure within the body.
  
  
  

B. Supportive Connective Tissue/Dense Connective Tissue

• It is composed of fibres as its main matrix element and is found in bones and cartilage.
• It provides connection between different tissues.
  
  
  

C. Fluid Connective Tissue

• It consists of liquid as the ground substance and is present throughout the body.
• It provides nutrition, helps in transport of nutrients and gets rid of waste matter.
  
  
  

Muscle Tissue

• Muscle tissue is one of the specialised tissues in animals.
• It is specialised to facilitate body movements.
  

Types of Muscle Tissue

 

  

 

 

 

Comparison of Smooth, Skeletal and Cardiac Muscles

 

 

Nervous Tissue

• Nervous tissue is the other specialised tissues in animals.
• It is specialised for the conduction of nerve impulses from one part of the body to another.
  
  
  

Types of Nerve Fibres