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Frog Nerve

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1. How does a CAP differ from a single action potential?
Single action potentials follow the “all or none” rule. The “all or none” rule being that if a stimulus is strong enough to depolarize the membrane of the neuron to threshold, then an action potential will be fired. Each stimulus that reaches threshold will produce an action potential that is equal in magnitude to every other action potential for the neuron. Compound action potentials do not exhibit this property since they are a bundle of neurons and have different magnitudes of action potentials. Compound action potentials are also graded, meaning the greater the stimulus, the greater the action potential. 2. Action potentials are said to be all or none responses. Why does the frog sciatic nerve give a graded response? 2. Action potentials are said to be all or none responses. Why does the frog sciatic nerve give a graded response?
The frog sciatic nerve gives a graded response de to the nerve being a bundle of axons and not a single axon, resulting in it not showing the “all or none” rule of an axon. In this experiment, if one axon is generating an action potential, then a small nerve impulse will be seen. If all axons are simultaneously generating action potentials, then a large nerve impulse will be seen. This means that the sciatic nerve impulse is graded due to it being able to be none, small, medium, large, or maximal. 3. What was the smallest voltage required to produce the maximum (largest) CAP? What proportion of the nerve fibers were excited to produce this maximal response? 3. What was the smallest voltage required to produce the maximum (largest) CAP? What proportion of the nerve fibers were excited to produce this maximal response?
To produce a maximum response, the whole nerve must be stimulated. If the stimulus voltage is increased slowly, you may observe discrete jumps in

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