Principles of Organisation

• Cell


  The basic building block of all living organisms

  
• Tissue


  A group of cells with a similar structure and function

  
• Organ


  Collections of tissues performing specific functions

  
• Organ system


  A system of organs which work together to form organisms

  
• Organism


  A living thing such as a plant, animal or single-celled life form

  
• Multicellular


  Organisms that are made of multiple cells

  
• Specialised cell


  A cell which has differentiated for a particular function

  
• Differentiation


  A process where a cell changes its structure to carry out a particular function

  
• Organelle


  A sub-cellular structure that carries out a specific function within a cell

  
• Examples of human tissues


  Muscular tissue and nervous tissue

  
• Examples of human organs


  Stomach and heart

  
• Examples of organ systems


  Digestive system and immune system

  
• Examples of plant tissues


  Epidermal tissue and palisade mesophyll

  
• Examples of plant organs

  Roots and stem