neurones

• label the neurone below

  a- dendrites

  b- nucleus

  c- cell body

  d- axon

  e- myelin sheath

  f- nodes of ranvier

  g- direction of nerve impulse

  
• Neurone


  • Adapted for its function of quickly transmitting across the nervous system
  • Changed shape to allow it to perform its function better
• Cell Body


  The nucleus which controls the activities of the neurone is surrounded by most of the cells cytoplasm
• Axon


  • A long extension of the cytoplasm which can be up to one metre in length so that nerve impulses can be transmitted from the CNS to the extremities of the body by one cell
• Insulating Sheath (Myelin Sheath)

  • A fatty layer around the axon produced by special cells
  • Acts as an insulator and helps transmit the nerve impulse much faster
  • Gaps in myelin are called Nodes of Ranvier
• Branched ends of the axon and small extensions from the cell body


  • Allow one neurone to make many connections with other nerve cells e.g. in the brain
• Student: Label the neurone below.