Transmission of synapses

• Cells that conduct nerve impulses are called neurons.

  The things that people think or feel, say and do are caused in one way or another by electrochemical events occuring within and between neurons that make up the nervous system, particulary those inside of the brain.
• STRUCTURE OF A NEURON

  
• Dendrites:

  Recieves the nerve impulse or signal from adjacent neurons

  Axons:

  Where electrical signals pass along

  Myelin sheath:

  Insulates and protects the axon from nerve influences that might affect the transmission of the nerve impulse down the axon.

  Terminal:

  Terminal buttons send signals to an adjacent cell.
• ALL OF THE NEURONS

  
• Motor neuron:

  • Carries messages from the CNS to the effectors such as the muscles and glands.
  • Short dendrites and also long axons.
• Relay interconnecting neurons:

  • Transfers messages from sensory neurons to other interconnecting neurons or motor neurons.
  • Short dendrites and long axons.
• Sensory neurons:

  • Carries messages from the PNS to the brain and the spinal cord.
  • Long dendrites and short axons.
• HOW A SYNAPSE WORKS

  
• HOW A SYNAPSE WORKS

  
• HOW A SYNAPSE WORKS

  
• An action potential occurs when a neuron sends information down a axon, away from the cell body.

  The action potential is an explosion of electrical activity - this means that in some event ( a stimulus) causes the resting potential to move forward.
• Dendrites on sensory neurons recieve information from environment.

  This creates an electrical impulse (action potential) which travels down an axon.

  This eletrical impulse is protected by external influences such as myelin sheath.

  When the electrical impulse reaches the axon terminal, the neuron releases a chemical into the synpatic cleft.

  The chemicals are then taken up to the receptor sites on the dendrites of the next neuron and the electrical impulse continues.