( 25 points) Consider an "alien" neuron that you have just measured as having: (1) an internal concentration of 28mMK+and 500mMNa+, and (2) an external concentration of 342mM K+and 86mMNa+. Your measurements also indicate that the membrane is not permeable to any other ions. (a) (5 points) What are the equilibrium membrane potentials EK and ENA, including the appropriate sign? (b) (5 points) A fellow researcher studying an identical neuron in a make-shift lab (there's a national emergency with many researchers scrambling to understand these cells because alien neurons have fallen to Earth!) comes over to you and says that she is seeing action potentials with a peak-to-peak amplitude of 130mV. Do you say (i) "that's great, very useful information," or (ii) "I don't think so, why don't you repeat your measurement and check the calibration on your amplifier and oscilloscope"? Why? (c) (5 points) Your colleague returns and she says, "I've checked my experimental setup and even repeated the measurement on another setup, and these neurons have action potentials with a peak-to-peak voltage of 130mV." You sheepishly remember that when you were originally measuring the cell concentrations you dropped your meter on your Double Double burger from In-N-Out (thereby getting that really yummy pinkish sauce all over your meter) just before measuring the external K+concentration. You measured the other three concentrations before this little mishap. Before re-measuring the external K+concentration you think a moment and then say either (i) that it will be higher than your original (and incorrect) measurement or (ii) lower than your original (and incorrect) measurement? Why? (d) (5 points) Aware of the mishap you are now convinced on the peak to peak amplitude. You now want to explore more on the ion channels. You see that the resting membrane potential of this alien neuron is found to be 38mV. Comment on how this can happen ? (e) (5 points) Your colleague claims that the Node of Ranvier's of this alien neuron have high density of Potassium ion channels. Do you think her claim is right