# Question: dr woodley is trying to explain the concepts of resting...

###### Question details

**Dr. Woodley is trying to explain the concepts of resting
membrane potential, equilibrium potential, and membrane potential
to the students in her laboratory. To do this, she uses a dish of
cultured motor neurons so that she can alter the solution covering
the cells and she can use a recording electrode to pierce one of
the cells and determine its membrane potential relative to the
extracellular fluid. She asks you a number of questions before and
after she alters the conditions around the cell.** The
normal media (fluid covering the cells) contains: 145 mEq/L
Na^{+} 5
mEq/L
K^{+} and
2 mEq/L Ca^{++}

and the intracellular fluid contains:

15 mEq/L
Na^{+} 155
mEq/L
K^{+} and
0.0001 mEq/L Ca^{++}**(12)**

1. List the factors that normally account for resting membrane
potential. **(3)**

2. Dr. Woodley then measures the resting membrane potential
(RMP) of the motor neurons and monitor that graphically displays
the charge indicates that it is -90 mV. What does this tell you
about the influence of the ions listed above on RMP? Why would this
occur? **(3)**

She then changes the media so that the new media is still
isotonic to the previous media, but it now contains 110 mEq/L
Na^{+}, 5 mEq/L K^{+}, and 27 mEq/L
Ca^{++}and she asks you the following questions:

3. Has the equilibrium potential changed for any of the ions? If
so, which ones changed, and which one did not?
**(3)**

4. Given the changes made to the media, would the resting
membrane potential of the cell change? Why? Or why not?
**(2)**