Nernst Equation (for cations): E(mV) - 61 log(C/C) Goldman Equation: E(m1) - 61 bog pk Na-+Palk) +Polch). P[K] + ). The following conditions apply to the next three questions: lon Intracellular Extracellular (MM) (mm) Permeability (rest) Permeability (Peak, AP) 25 Na 12 142 0.04 K 118 4,0 1.0 4.0 CH 10 110 0.5 0.5 1. What is the resting membrane potential for the conditions given above? (2 points) 2. Using the peak (Action Potential) permeabilities what is the calculated membrane potential (realizing that the peak permeabilities do not coincide, therefore this is a theoretical number) (2 points) 3. A neurotransmitter is released in the region of the axon hillock that causes a local change in membrane permeabilities via ligand-gated ion channels as shown below (compare to the above table for normal rest values) (5 points) lon Permeability (with transmitter) Na 0.08 K 1.0 CH 0.5 a) What is the resultant membrane potential when this substance is present? b) Does this neurotransmitter cause an EPSP or an IPSP? c) What is the magnitude of the EPSP or IPSP (how many mV) d) How much bigger (by what percentage) is the new voltage