Plant Cell Specialisation

• What is the process called when cells become specialized?

  Differentiation
• How are root hair cells specialized for their function?

  • Increase surface area for water absorption
  • Lack chloroplasts as they are underground
• What do root hairs do for the root cells?

  Increase surface area for absorption
• Why do root hair cells not contain chloroplasts?

  They are underground and do not photosynthesize
• What are the key features of xylem cells?

  • Thick walls containing lignin for support
  • End walls broken down to form long tubes
  • No nucleus, cytoplasm, vacuole, or chloroplasts
• What chemical is found in the walls of xylem cells?

  Lignin
• What is the function of xylem cells?

  Carry water and dissolved minerals
• How are phloem cells specialized for their function?

  • Consist of phloem vessel cells and companion cells
  • Vessel cells have no nucleus and limited cytoplasm
  • End walls have sieve plates for sugar movement
• What do phloem vessels transport?

  Dissolved sugars
• What are sieve plates in phloem vessel cells?

  Pores in the end walls for sugar movement
• What is the role of companion cells in phloem?

  Provide energy to phloem vessel cells
• What do phloem vessel cells lack?

  No nucleus and limited cytoplasm
• What are the main differences between xylem and phloem cells?

  • Xylem: transports water and minerals, has thick walls with lignin
  • Phloem: transports sugars, has sieve plates and companion cells