synapses and reflexes

• Synapse

  Connects neurons
• Synapses connect neurons
• Reflexes help prevent injury
• Reflex arc

  1. Stimulus detected by receptors

  2. Impulses sent along sensory neuron

  3. Impulses reach synapse between sensory and relay neuron

  4. Chemicals released at synapse

  5. Impulses sent along motor neuron

  6. Effector (muscle) contracts
• Reflex arc goes through the central nervous system
• Reflex actions bypass conscious brain when a quick response is essential