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Discussion on action potentials

Describe an action potential and its representation on an EGG, labeling all activity.

Compare the divisions of the autonomic nervous system's effect on heart rate and stroke volume.

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An action potential is a result of a complex set of cellular responses to a stimulus. The cellular responses involves movement of ions (specifically sodium and potassium, both are positively charged) back and forth across the cellular membrane. The movement is controlled by membrane proteins specific to those ions.
The whole process can be simplified to four main parts:

1) Resting potential- when the neuron is not stimulated, it is said to be at resting potential. Inside the neuron is negative when compared to the outside. This is due to the relative concentrations of different ions when compared across the cell membrane. Remember that the cell membrane is selectively permeable -- only certain materials can pass freely across the membrane; most ions and larger molecules need membrane proteins to act as channels or pumps and move them across. So when you take into account the numbers of negatively and positively charged molecules and ions inside the cell vs. outside the cell, the overall charge of the inside of the cell is negative. The resting potential of a neuron is normally ...

Solution Summary

In this solution, I breakdown the action potential in a nerve cell and discuss the different parts. I also briefly discuss nervous control of heart rate and stroke volume.