Electrical Activity of Neurons This worksheet compliments the ​
Click and Learn Electrical Activity of Neurons d
​eveloped at the HHMI website. Answer the following questions as you proceed through the activity slides. Watch the video on slide 1 and answer the following questions. 1. What is a neuron? 2. What is a synapse? 3. Summarize the steps that begin with the impulse information coming down to the synapse and ending with the propagation of the impulse from one neuron to the next. 4. Aplysia​
is a snail (see image on the right), that serves as an excellent model organism for studying neurons. What is graphed on the x and y axes when measuring neuronal activity? 5. Slide 3 mentions both sensory and motor neurons. Describe what each of these neurons are focusing on the difference between these two types of neurons. 6. Using the information on slides 4,and 5 what is a threshold value and how does it impact the action potential? 7. Observe the neuron traces of the voltages from the sensory neuron and the motor neuron on slide 7. Which neuron comes first in the circuit pathway? 8. After viewing the short video on slide 8 explain why there are no traces of any voltage changes in the motor neuron, while there are voltage changes measured in the sensory neuron. 9. View the short video on slide 9. An action potential is achieved in the sensory neuron. Why is it achieved here and was not achieved in slide 8? 10. Describe the voltage change that is recorded in the motor neuron on slide 9. Explain why no action potential is achieved in this neuron. 11. Summarize what is learned about synaptic potentials on slide 10. 12. In order to understand the video in slide 11, read ​
this wikipedia link ​
on neuromodulation. Summarize the role that neuromodulation plays in neuronal activity. 13. Watch the video on slide 11. Summarize ( you may use a diagram to do this) the connections that would be made in vitro (outside of the body) between modulatory, motor and sensory neurons. 14. How were the scientists able to use only 2 neurons to simulate this circuit? What 2 neurons were used and how did they account for the missing neuron? 15. What is the difference that is observed between puffing on serotonin once and puffing 5 times? 16. When inhibitors of protein synthesis were applied to this pathway which memory was affected long term or short term memory? 17. Watch the video on slide 12 and summarize the difference in synaptic activity before and after serotonin has been introduced. 18. What does this suggest to you about the role that serotonin plays in learning and memory?