Which of the following is true about the flow of energy within ecosystems? A.
Energy flows both ways between living systems and the physical environment.
B.
Energy flows from the physical environment into living systems only.
C.
Energy does not flow between living systems and the physical environment.
D.
Energy flows from living systems into the physical environment only.

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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answer; the correct answer is (beta)

the answer is c.) there is a warm front in region a and a stationary front in region b.