The mother has brown-colored fur on its ears, the father has white-colored fur on its ears, and the offspring is born with white-colored fur on one ear and brown-colored fur on the other ear. Which explains the reason for this difference?

Active site is where they touch.

Na+ loss through sweet plus the dilution has lowered na+ concentration outside of neurons, altering the na+ equilibrium potential. sodium exists more outside the cells than inside. when na+ is lost by sweat plus the dilution( because they drink a lot of water) changes the concentration outside the cell, forcing the water to enter the cell and attempt to balance the concentration inside/outside.the problem is that the abundance of water will cause the cells to swell. most cells can adapt, however, the brain cells can't that's why the runner has confusion and can't control the muscles.  if not treated and this occurs in less than 48 hours, it can be immediately fatal .

The answer is metamorphic.