specialisation differentiation

• Cell specialization

  The process where cells gain new sub-cellular structures to be suited to their role
• Specialized animal cells

  • Sperm cells
  • Nerve cells
  • Muscle cells
• Specialized plant cells

  • Root hair cells
  • Xylem cells
  • Phloem cells
• Cell differentiation

  The process where stem cells switch on or off certain genes to become specialized cells
• In animals, most cells differentiate early and lose the ability, while in plants many cells retain the ability to differentiate throughout life
• SPERM CELL

  Function

  To get DNA into an egg cell

  • Tail for swimming
  • Lots of mitochondria to provide energy
  • Enzymes in head to digest egg cell membrane
• NERVE CELL

  Function

  Carries messages around the body at high speed

  Specialisations

  • Fatty sheath speeds up message transport
  • Long, so it can carry messages over a distance
• ROOT HAIR CELL

  Function

  Helps a plant absorb water and minerals from soil

  Specialisation

  A long and thin extension gives a large surface area for absorption
• MUSCLE CELLS

  Function

  Create movement by contracting and relaxing

  Specialisations

  • Long protein strands that can slide over each other to shorten/lengthen the cell
  • Lots of mitochondria to generate energy
• XYLEM

  Function

  Form tubes that transport water and minerals in plants

  Specialisation

  They're dead cells with holes at either end - water and minerals can just flow through them
• PHLOEM

  Function

  Tubular cells that transport dissolved sugars in a plant

  Specialisations

  • Few subcellular structures so sugars flow through easily
  • Pores in end walls to let sugars through