ANSWER Potassium ions enter the neuron and diffuse to adjacent areas resulting

Answer potassium ions enter the neuron and diffuse to

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ANSWER: Potassium ions enter the neuron and diffuse to adjacent areas, resulting in the opening of voltage-gated sodium channels farther down the axon. Sodium ions enter the neuron and diffuse to adjacent areas, resulting in the opening of voltage-gated potassium channels farther down the axon. Sodium ions enter the neuron and diffuse to adjacent areas, resulting in the opening of voltage-gated sodium channels farther down the axon. Potassium ions enter the neuron and diffuse to adjacent areas, resulting in the opening of voltage-gated potassium channels farther down the axon.
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12/1/2018 BIOL 1030 Assignment 6 52/75 Correct The membrane potential measures the difference in the electrical potential (voltage) across the neuron’s plasma membrane. When the membrane potential of a neuron decreases, the negative value of the electrical potential across the plasma membrane is reduced and the membrane potential becomes more positive. Chapter 48 Misconception Question 5 Part A What causes the falling phase of the action potential? Select the best answer. Hint 1. What causes the charge inside the cell drop? What causes the ion channels open and close? ANSWER: becomes neutral remains unchanged becomes more negative becomes more positive the opening of voltage-gated potassium channels the opening of voltage-gated sodium channels Voltage-gated potassium channels inactivate soon after opening, halting potassium inflow. inactivation of voltage-gated sodium channels and the opening of voltage-gated potassium channels
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12/1/2018 BIOL 1030 Assignment 6 53/75 Correct Voltage-gated sodium channels inactivate soon after opening, halting Na + inflow, and most voltage-gated potassium channels open, causing a rapid outflow of K + . Both events combine to cause the falling phase of the action potential. Chapter 48 Misconception Question 3 Part A Why is an action potential an all-or-none response to stimuli? Hint 1. What would happen if action potential were able to travel backwards? What prevents that from happening? ANSWER: Correct If a depolarization opens voltage-gated sodium channels, the resulting flow of Na + into the neuron results in further depolarization. Chapter 48 Misconception Question 4 Part A because voltage-gated ion channels open when membrane potential passes a particular level because neurons contain gated ion channels that are either open or closed If a depolarization opens voltage-gated potassium channels, the resulting flow of K + into the neuron results in further depolarization. because a typical neuron receives signals through multiple dendrites but transmits signals through a single axon
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12/1/2018 BIOL 1030 Assignment 6 54/75 The plasma membrane of a neuron has voltage-gated sodium and potassium channels. What is the effect of membrane depolarization on these channels?
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