specialised cells

• Animal cell specialization

  Most animal cells are specialized with adaptations to carry out a specific function
• Sperm cell

  • Contains half the genetic information
  • Has a long tail
  • Streamlined
  • Packed with mitochondria and enzymes
• Nerve cell


  • Sends electrical impulses around the body
  • Has a long axon
  • Covered in myelin which insulates the axon and speeds up transmission
  • Dendrites increase surface area for connections
• Muscle cell


  • Can contract and relax
  • Contain protein fibers that can change length
  • Packed with mitochondria
  • Work together to form muscle tissue
• Root hair cells

  • Hairs increase surface area
  • Don't contain chloroplasts
• Xylem

  • Have very thick walls containing lignin
  • Xylem cells die
  • Ends between cells completely break down for easy flow of water and minerals
• Phloem


  • Contain phloem vessel cells with no nucleus
  • Have pores called sieve plates to allow flow of dissolved sugars
  • Each phloem vessel cell has a companion cell that provides energy
• Bacterial division


  1. Bacteria multiply by simple cell division (binary fission)

  2. Can do this once every 20 minutes

  3. Allows rapid reproduction
• Stem cells


  • Undifferentiated cells that can be found in bone marrow or embryos
  • Useful in treating leukemia by forming new blood cells
• xylem - phloem

  xylem cells are dead cells phloem cells are alive phloem tubes have pores at the end xylem tubes are hollow xyelm transports water minerals Phloem transports sugars and waterv

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