Control and coordination in mammals — practice question

Fig. 7.1 shows a synapse linking a chemoreceptor cell from a human taste bud with a dendrite of a sensory neurone. In an experiment, the microvilli of the chemoreceptor cell were exposed to different concentrations of sodium chloride solution. For each concentration, the membrane potential of the chemoreceptor cell and that of the sensory neurone dendrite were measured. The resting potential of this chemoreceptor cell is $-50\,\text{mV}$ and the resting potential of the dendrite of this sensory neurone is $-70\,\text{mV}$. The results are given in Table 7.1, with sodium chloride concentrations in $\text{g dm}^{-3}$ and membrane potentials in $\text{mV}$.