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Measuring the Resting Membrane Potential

  • In a resting axon, the distribution of cations and anions polarizes the plasma membrane. The intracellular fluid (ICF) becomes relatively negative to the extracellular fluid (ECF).
  • A image descriptionvoltmeter is used to measure the charge difference (voltage or elec-trical potential) between the ECF and ICF. The greater the difference, the greater the voltage.
An image showing how to measure the resting membrane potential using voltmeter with 2 electrods
An image showing how to measure the resting membrane potential using voltmeter (which is labeled) with 2 electrods
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An image showing how to measure the resting membrane potential using voltmeter (which is labeled) with 2 electrods
An image showing a ground electrod of voltmeter placed on the surface of a neuron cell membrane
An image showing a ground and recording electrods of voltmeter placed on the surface of a neuron cell membrane
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  • The recording electrode typically consists of a glass tube filled with KCl solution and a silver wire coated with Ag/AgCl. The electrode is able to convert ionic current to electrical current, which is sent to the voltmeter.
  • The ground electrode is image descriptionplaced outside the membrane and the recording electrode is inserted image descriptionrecording electrode into the axon.
An image showing a ground electrod of voltmeter placing on the surface of a neuron cell membrane
An image showing a ground electrod of voltmeter placing on the surface of a neuron cell membrane
An image showing a ground electrod of voltmeter placing on the surface of a neuron cell membrane
An image showing a ground electrod of voltmeter placing on the surface of a neuron cell membrane
An image showing a ground electrod of voltmeter placing on the surface of a neuron cell membrane
An image showing a ground electrod of voltmeter placing on the surface of a neuron cell membrane
An image showing a ground electrod of voltmeter placing on the surface of a neuron cell membrane
An image showing a ground electrod of voltmeter placing on the surface of a neuron cell membrane
An image showing a recording electrod of voltmeter insertion inside the membrane of a neuron cell membrane
An image showing a recording electrod of voltmeter insertion inside the membrane of a neuron cell membrane
An image showing a recording electrod of voltmeter insertion inside the membrane of a neuron cell membrane
An image showing a recording electrod of voltmeter insertion inside the membrane of a neuron cell membrane
An image showing a recording electrod of voltmeter insertion inside the membrane of a neuron cell membrane
An image showing a recording electrod of voltmeter insertion inside the membrane of a neuron cell membrane
An image showing a recording electrod of voltmeter insertion inside the membrane of a neuron cell membrane
An image showing a recording electrod of voltmeter insertion inside the membrane of a neuron cell membrane
  • Charge differences between the ECF and ICF (resting membrane potential or RMP) are image descriptiondisplayed in millivolts (mV) on the voltmeter.
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods
An image showing the resting membrane potential on board using voltmeter with 2 electrods