All of the following are TRUE except: a. The environment contains all the materials and energy needed for living organisms to carry out their life activities
b. Living things and their environment affect each other
c. Ecology examines how everything is connected
d. Non-living things cannot affect living things in an environment.

d

Explanation:

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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