Recitation Materials

To view the video recitations, click the numbered pages above.

Pre-Lab Questions

• Recitation 1 - Intro/Membrane Tutorial /Equilibrium Potential

• Recitation 2 - Na Action Potential/ Threshold

• Recitation 3 - Voltage Clamping/ Chattering Ion Channels

• Recitation 4 - Neuromuscular Junction

• Recitation 5 - Dynamical View of Threshold

• Recitation 6 - Passive, Unmyelinated and Myelinated axons
• Recitation 7 - Na/K channel kinetics tutorial, No Pre-Lab in lieu of Quiz 1
• Recitation 8 - No Pre-Lab in lieu of Quiz 2

Helpful Materials for Review

• Ionic Mechanisms and Action Potentials Online textbook chapter from the University of Texas at Houston with good graphical representations
• Resting Potentials and Action Potentials Another chapter from UT
• Resistance(Interactive) See how variables like diameter and length effect resistance
• Reversal Potential
  

• Nernst Equation
  

See how the equation form of Ohm's law relates to a simple circuit. Adjust the voltage and resistance, and see the current change according to Ohm's law. The sizes of the symbols in the equation change to match the circuit diagram. Wikipedia Review Ohm's Law

• Wiki Voltage
• Wiki Current
• Wiki Conductance
• Capacitance

• Nernst/Goldman Equation Simulation (Thank Tom for finding this one!)

The University of Arizona College of Medicine has a nice description of the Nernst equation. The Nernst equation (named after its originator, the German Chemist and Nobel laureate, Walther Nernst), provides a quantitative measure of the equality that exists between chemical and electrical gradients and is the starting point for understanding the basis of the "membrane potential."

The Goldman-Hodgkin-Katz equation (named in honor of American David Goldman and the British Nobel laureates Sir Alan Hodgkin and Sir Bernard Katz; frequently simply referred to as "the Goldman equation" calculates an estimated membrane potential that reflects the relative contributions of the chemical concentration gradients and relative membrane permeability for K+, Na+ and Cl-.

Ion ConcentrationsFor each ion (i.e., K+, Na+ and Cl-) a slider is provided to adjust one of three parameters. Two of these sliders control the intracellular and extracellular concentrations of the ion in question, and these can be varied between values of 1 mM and 600 mM. All slider values can be adjusted by double clicking on the value reported in the slider box and typing in the desired value. The default values are: for K+, 10 mM out and 100 mM in; for Na+, 100 mM out and 10 mM in; and for Cl-, 100 mM out and 10 mM.