Remember how we mentioned that the dichotomous key we provided was only designed for use with organisms A-E in the chart? If we add another organism such as the cat below, you will find that the dichotomous key cannot arrive at the scientific name, Felis catus, for this cat. In the space below, please redesign the dichotomous key so that it includes the cat. You can still reuse steps as the key should now be able to arrive at all organisms A-F.

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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i don't know. if i were you, i would search it up online : d