NEURONS

• What are the three neurons?

  sensory, relay and motor
• how are signals transmitted?

  electrically and chemically
• what is the function of a sensory neuron?

  carries messaged from receptors in the PNS to CNS
• what does a sensory neuron look like?

  axon branches into two extensions within the cell body in the middle
• what is the function of the relay neuron?

  connect sensory neurons to motor or other neurons in the CNS
• what does a relay neuron look like?

  short dendrites and axons
• what’s is the function of a motor neuron?

  connect the CNS to effectors (muscles or glands)
• what does a motor neuron look like?

  short dendrites and long axons
• what is the soma (cell body)?

  includes a nucleus which contains the genetic material of the cell, produces the proteins for the cell
• what are dendrites?

  branch-like structures that protrude from the cell body
• what do dendrites do?

  carry nerve impulses from neighbouring neurons towards the cell body
• what does the axon do?

  carries impulses away from the cell body
• What is myelin sheath?

  fatty layer that insulates and protects the axon
• what are terminal buttons?

  at the end of the axon, they communicate with the next neuron across the synapse
• what is the synapse?

  the gap between neurons where chemical transmission takes place
• What is electrical transmission?

  when a neuron is in its resting state the inside of the cell is negatively charged compared to the outside

  when a neuron is activated, the inside of the cell becomes positively charged for a split second, causing an action potential. Creates an electrical impulse that travels down the axon to the end of the neuron