Exercise 3: Neurophysiology of Nerve Impulses: Activity 9: The Action Potential: Putting It All Together Lab Report Pre-lab Quiz

Results You scored 100% by answering 4 out of 4 questions correctly.

1. Sensory neurons respond to an appropriate sensory stimulus with a change in membrane potential that is You correctly answered: b. graded with the stimulus intensity.

2. If the depolarization that reaches the axon is large and suprathreshold, the result in the axon is You correctly answered: c. action potentials at higher frequency.

3. At the axon terminal, each action potential causes the release of neurotransmitter. This neurotransmitter diffuses to the receiving end of an interneuron, where it binds to receptors and causes …show more content…

You correctly answered: d. All of the above play a role in determining the frequency of action potentials in the axon of the interneuron.

Review Sheet Results

1. Why is the resting membrane potential the same value in both the sensory neuron and the interneuron? Your answer: Both the resting membrane potential and the sensory neuron and interneuron have a resting potential value of -70mv

2. Describe what happened when you applied a very weak stimulus to the sensory receptor. How well did the results compare with your prediction? Your answer: There was a very small response in the R1 receptor, but the other 3 showed no response. This agreed with my prediction.

3. Describe what happened when you applied a moderate stimulus was to the sensory receptor. How well did the results compare with your prediction? Your answer: All of the receptors had a response, but R1 and R3 had the larger graded potentials. This disagreed with my prediction that a small depolarization would occur at R1 and R2 with APs happening at R3 and R4

4. Identify the type of membrane potential (graded receptor potential or action potential) that occurred at R1, R2, R3, and R4 when you applied a moderate stimulus (view Experiment Results to view the response to this stimulus). Your answer: Graded receptor potential at R1 and R3 with APs at R2 and R4.

5. Describe what happened when you applied a strong stimulus to the sensory receptor.