Cell Differentiation and Specialisation

• Cell Differentiation


  The process by which a cell changes to become specialised for its job
• Cells


  • They don't all look the same
  • They have different structures to suit their different functions
• Cell Differentiation


  1. Undifferentiated cell

  2. Differentiated cell
• As cells change, they develop different subcellular structures and turn into different types of cells
• This allows them to carry out specific functions
• Differentiation in mature animals


  • Mainly used for repairing and replacing cells, such as skin or blood cells
• Stem cells


  Undifferentiated cells
• Sperm cells


  • Long tail and streamlined head to help it swim to the egg
  • Lots of mitochondria to provide the energy needed
  • Carries enzymes in its head to digest through the egg cell membrane
• Nerve cells


  • Long (to cover more distance)
  • Branched connections at their ends to connect to other nerve cells and form a network throughout the body
• Muscle cells


  • Long (so that they have space to contract)
  • Contain lots of mitochondria to generate the energy needed for contraction
• Root hair cells


  • Grow into long "hairs" that stick out into the soil
  • Gives the plant a big surface area for absorbing water and mineral ions from the soil
• Phloem and xylem cells


  • Form phloem and xylem tubes to transport substances such as food and water around plants
  • Phloem cells are long and joined end to end
  • Xylem cells are hollow in the centre and phloem cells have very few subcellular structures, so that stuff can flow through them