Cell Organisation

1. Cells are the basic building blocks of life, that make up all living organisms. 

2.  Specialised cells carry out a particular function. 

3. The process by which cells become specialised for a particular job is called differentiation. Differentiation occurs during the developement of a multicellular organism. 

4. These specialised cells form tissues, which form organs, which form organ systems. 

5. Large multicellular organisms have different systems inside them for exchange and transporting materials. 

In mamals (like humans), examples of tissues include; 

- Muscular tissues, contract (shortens) to move whatever it's attached to. 

- Gladular tissue, makes and secretes chemicals like enzymes and hormones. 

- Epthilial tissue, which covers some parts of the body. 

For example, the stomach is an organ made of these tissues:

- Muscular tissue, which moves the stomach wall to churn up food. 

- Gladular tissue, which makes digestive juices to digest food. 

- Epithelial tissue, which covers the outside and inside of the stomach.