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Measurement of Compound Action Potentials from the Frog Sciatic Nerve

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Measurement of Compound Action Potentials from the Frog Sciatic Nerve
Abstract:
The purpose of this experiment was to examine how the compound action potentials propagate down the sciatic nerve of a frog based on varying stimuli. Before the nerve could be tested it needed to be extracted from the thigh of the frog and then submerged in saline. Several varying stimuli were used and recorded by a software package. The second experiment requires a constant stimulus with varying reference pin locations. From this the velocity of the action potential propagated can be determined. The experiment revealed that as the intensity of the stimulus increased so did the intensity of the compound action potential (CAP).
Introduction:
As taught to us during class different stimuli are going to have different effects on the force the muscle generates. The muscle first had to be extracted. Dissection involved the use of scalpels, scissors, and tweezers to cut and remove both the skin and the muscle. While removing the This experiment will allow us to analyze how the action potentials generated by a nerve from a frog changes in response to differences in amplitude of a stimulus from a voltage source. By analyzing the changes in action potential, we will be able to determine whether there is a certain trend in the action potentials and whether or not the nerve will reach a saturation point at which there will no longer be a change in the value of the action potential. Also, we will analyze the change in speed of the propagation of the action potential due to alterations in amplitudes of the stimuli. We predict this speed of propagation to be between 0 and 80 meters per second.
Methods:
At the beginning of this lab, a frog was soaked in a paralyzing agent and then pithed. This is done to not create any discomfort for the frog and euthanize them in the quickest and least painful way possible. After the animal is pithed, the dissection can begin. First, the skin of the animal must be removed off the legs. Simply cut around the torso and “de-pants”

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