Cell differentiation

• Cell differentiation


  When an unspecialised cell becomes a more specialised cell type
• Multicellular animals and plants must differentiate so cells can fulfil specific roles
• Palisade mesophyll cells


  • Carry out photosynthesis
• Spongy mesophyll cells


  • Allow gases to circulate and exchange
• Guard cells


  • Open and close to control exchange of gases
• Phloem (sieve tubes)


  • Transport sugars to other parts of the plant
• Companion cells


  • Provide energy for transporting substances in sieve tubes
• Xylem (xylem vessels)


  • Transport water and dissolved minerals from roots up the plant
• Growing meristem


  • Produce new cells as they divide
• Photosynthesis


  The process by which plants use sunlight, water and carbon dioxide to create oxygen and energy in the form of sugar
• Mitosis


  Cell division that produces two genetically identical daughter cells
• Stem cells


  Unspecialised cells that have the ability to develop into different cell types
• Cell division in plants occurs in meristems
• The main meristems are at the tip of the shoot and root
• Cells of the meristem differentiate to produce all types of plant cells
• DNA is the genetic material that contains the instructions for life
• Chromosomes are structures in the nucleus that contain DNA
• Genetics is the study of heredity and the variation of inherited characteristics
• Stem cells are not yet specialised (undifferentiated)