What do you think is likely to happen if the sphincter at the base of the esophagus does not function properly?

Whenever sphincter at the base of the esophagus does not function properly this will lead to the reflux of food and stomach acids that is flow of food and stomach to backwards into the esophagus and this eventually leads to the inflamation and irritation of the esophagus lining as a results of the acids reflux, and at the end leads to burning chest or at times sour taste or cough

and anyone suffering from this is said to have a Gastroesophageal reflux disease (GERD)

the answer that best describes the relative refractory period in the neuron is the resting membrane potential is restored, but concentrations of sodium and potassium are not restored to their original state.

the refractory period is the time during which another stimulus given to the neuron will not lead to a second potential. thus, because na+ channels are inactivated during this time, additional depolarizing stimuli do not lead to new action potentials.  

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