Process of Synaptic Transmission

• What is the first step in the process of synaptic transmission?

  The action potentials are sent down the axon until they reach the presynaptic terminal.
• What happens to neurotransmitters when they are released into the synaptic cleft?


  They diffuse across the synapse from high to low concentration.
• Where are neurotransmitters stored before they are released?


  In vesicles located in the presynaptic neuron.
• How do neurotransmitters interact with the postsynaptic neuron?


  They bind with specific receptor sites that are only present on the postsynaptic neuron.
• What determines whether the next neuron will fire after neurotransmitter binding?


  Whether the neurotransmitter has an excitatory or inhibitory effect.
• What is the process called when neurotransmitters are recycled to be stored in vesicles?


  Reuptake.
• What are the two possible effects of neurotransmitters on the next neuron?


  They can either prepare the next neuron to fire or be recycled.
• What type of neurotransmitter is noradrenaline?


  Excitatory neurotransmitter.
• What is the role of excitatory neurotransmitters in the central nervous system?


  They make it more likely that the next neuron will fire, increasing brain activity.
• What is one example of an excitatory neurotransmitter?


  Noradrenaline.
• What is summation in the context of synaptic transmission?


  • Occurs when two neurons synapse at the same postsynaptic neuron.
  • Excitatory and inhibitory influences are added together.
  • If the overall effect is mainly inhibitory, it reduces the likelihood the neuron will fire.
  • If it is mainly excitatory, the impulse will fire.
• What type of neurotransmitter is serotonin?


  Inhibitory neurotransmitter.
• What is the effect of inhibitory neurotransmitters on the next neuron?


  They prevent or reduce the likelihood that the next neuron will fire.
• What is one example of an inhibitory neurotransmitter?


  Serotonin.
• What are the effects of low and high levels of serotonin?


  Low levels cause:

  • Low mood
  • Depression
  • Aggression
  • Sleep problems
  • Low energy
  • Poor concentration

  
  

  High levels cause:

  • Happiness
  • Risk-taking behavior
  • Nervousness
  • High blood pressure
• What are the effects of low and high levels of noradrenaline?


  Low levels cause:

  • Low mood
  • Depression
  • Aggression
  • Sleep problems
  • Low energy
  • Poor concentration

  
  

  High levels cause:

  • Happiness
  • Risk-taking behavior
  • Nervousness
  • High blood pressure
• What is the role of neurotransmitters in the brain?


  They act as chemical messengers.
• How do drugs affect neurotransmitter levels?


  They can increase or decrease levels of neurotransmitters.
• How do drugs work in relation to neurotransmitters?


  They affect the transmission of neurotransmitters across the synapse.