Neurons

• Neurons


  Nerve cells that process & transmit messages via electrical impulses.
• Motor neurons


  Connects to central nervous system to effectors such as muscles and glands.
• Sensory neurons


  Carries messages from peripheral nervous system to the central nervous system.
• Relay neurons


  Connect sensory neurons to motor neurons.
• Structure of neurons

  Axon: carries impulse.

  Myelin sheath: fatty layer that protects and insulates the axon and speeds up electrical transmission.

  Nodes of ranvier: Speeds up transmission by forcing it to jump across the gaps in an axon.
• Synaptic transmission

  Action potential moves down the axon to the pre-synaptic terminal where it stimulates the synaptic vesicles which then carry the action potential across the synaptic gap into the post-synaptic neuron where it either has an excitatory effect (increases the chance of the neuron firing) or an inhibitory effect (decrease the chance of the neuron firing.)