the reflex arc

• What cells are responsible for quick reactions to pain?

  Neurons
• What structure do neurons form to facilitate quick reactions?

  A reflex arc
• What are the three types of neurons in a reflex arc?

  • Sensory neuron
  • Relay neuron
  • Motor neuron
• What color represents the sensory neuron in the diagram?

  Blue
• Where is the cell body of the relay neuron located?

  In the spine
• What is the function of the axon in a neuron?

  To carry information across the body
• What are the axon terminals responsible for?

  Converting electrical signals to chemical signals
• What is the structure called where axon terminals almost touch dendrites?

  The synapse
• What is the role of the myelin sheath?

  To protect the cell and increase transmission speed
• What is the muscle at the end of the motor neuron called?

  The effector
• What are the steps in the reflex arc process?

  1. Sensation detected by sensory receptors
  2. Electrical signal travels along dendrite to axon
  3. Signal converts to chemical at axon terminal
  4. Chemical crosses synapse to relay neuron
  5. Relay neuron sends signal to motor neuron
  6. Motor neuron activates effector (muscle)
• What happens when the signal reaches the motor neuron?

  It activates the effector muscle
• How does the brain process information during a reflex action?

  After the body has already moved
• What is the fastest neuron in the body?

  The alpha motor neuron
• How fast does the alpha motor neuron transmit information?

  119 meters per second
• What is proprioception?

  Awareness of body position in space
• What is the speed of type C neurons that transmit pain?

  One mile per hour
• Why are type C neurons slow?

  They are smaller and unmyelinated
• What resources are available for psychology students?

  • Over 140 educational videos
  • Website with additional resources
  • Support for teachers and students