Specialised cells and differentiation

• What is the process by which a cell changes to become specialised?

  Differentiation
• Why do cells differentiate?

  To become specialised for their job
• What happens to most animal cells after they become specialised?

  They lose the ability to differentiate
• What type of cells retain the ability to differentiate throughout their life?

  Plant cells
• What is the main purpose of differentiated cells in mature animals?

  Repairing and replacing cells
• What are undifferentiated cells called?

  Stem cells
• What is the primary function of sperm cells?

  • To deliver male DNA to female DNA
• How do sperm cells assist in reproduction?

  By swimming to the egg
• What structural features help sperm cells swim?

  A long tail and streamlined head
• Why do sperm cells contain many mitochondria?

  To provide energy for swimming
• What do sperm cells carry in their head?

  Enzymes to digest the egg membrane
• What is the primary function of nerve cells?

  • To carry electrical signals throughout the body
• How are nerve cells structured to perform their function?

  They are long with branched connections
• What is the primary function of muscle cells?

  • To contract quickly
• Why are muscle cells long?

  To allow space for contraction
• What do muscle cells contain to generate energy?

  Lots of mitochondria
• What is the primary function of root hair cells?

  • To absorb water and minerals
• How do root hair cells increase absorption efficiency?

  By growing long "hairs" into the soil
• What do phloem and xylem cells transport?

  Food and water around plants
• How are phloem and xylem cells structured for their function?

  • Long and joined end to end
  • Xylem cells are hollow
  • Phloem cells have few subcellular structures
• Why don't all cells contain all subcellular structures?

  Some cells don't need certain structures
• Why don't root hair cells need chloroplasts?

  They don't photosynthesise underground