The Importance of Cell Differentiation
- As a multicellular organism develops, its cells differentiate to form specialised cells
- Specialised cells have structural adaptations which enable them to perform specific functions within the organism
- Almost all of the cells in a multicellular organism will contain the same genetic information (the same genes or alleles), but each cell will have a different set of active genes which determine how the cell functions
- When the cell differentiates, these active genes cause the development and composition of subcellular structures which enables it to carry out a certain function
- e.g. To form a nerve cell the cytoplasm and cell membrane of an undifferentiated cell must elongate to form connections over large distances
Diagram showing the differentiation of a human cell
Cell Differentiation in Plants and Animals
- In an animal, most cells differentiate at an early stage of its development. Cell division is mainly restricted to repair and replacement in mature animals
- Animal cells therefore lose their ability to differentiate after they have become specialised early in the life of the animal
- Some cells in various locations throughout the body of an animal retain the ability to differentiate throughout the life of the animal. These cells are called adult stem cells and are mainly involved in replacing and repairing cells (such as blood or skin cells)
- Plants differ from animals in that many types of plant cell retain the ability to fully differentiate throughout the life of a plant, not just in the early stages of development
