About how much energy’s lost when an organism consumes another organism from a different trophic level?

10 percent of energy is transferred to the next level of organisms so that would lead me to believe that 90 percent of the energy is lost.

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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