plant cell specialisation

• What are the three specialized plant cells discussed?

  Root hair cells, xylem cells, phloem cells
• What is the process called when cells become specialized?

  Differentiation
• What are the key structures of a general plant cell?

  Chloroplasts, cellulose cell wall, permanent vacuole
• 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 increase in root hair cells?

  Surface area
• 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 thick walls of xylem cells?

  Lignin
• What is the function of xylem cells?

  To carry water and dissolved minerals
• What happens to xylem cells when they are sealed with lignin?

  They die
• What do phloem tubes transport?

  Dissolved sugars
• What are the key features of phloem cells?

  • Consist of phloem vessel cells and companion cells
  • Phloem vessel cells have no nucleus and limited cytoplasm
  • End walls have sieve plates for sugar movement
• 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
• How do the structures of xylem and phloem cells differ in function?

  Xylem transports water; phloem transports sugars
• How does the lack of internal structures in xylem cells benefit their function?

  It allows easier flow of water and minerals
• What adaptations do root hair cells have for water absorption?

  • Long, thin shape increases surface area
  • No chloroplasts as they are underground
• Compare the roles of xylem and phloem in plants.

  • Xylem: Transports water and minerals from roots to leaves
  • Phloem: Transports sugars throughout the plant