Organisation of Cells (SQA National 5 Biology): Revision Note

Specialised cells

• A specialised cell is a cell that has a structure that aids its specific function

  • This could relate to cell shape or the combination of cellular structures present within the cell

• Cells specialise by undergoing a process known as differentiation

• When a cell differentiates, it synthesizes organelles and new features which enable it to carry its required 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

• Examples of specialised cells in animals include:

  • Sperm cells

  • Egg cells

  • Nerve cell

Levels of organisation

In complex multicellular organisms:

• Cells are specialised to carry out particular functions

• These specialised cells work together to form tissues

• The tissues form organs

• The organs work together to form organ systems