The portion of the Earth and its atmosphere that can support life. The part of the global carbon cycle that includes living organisms and biogenic organic matter.

Biosphere

Explanation:

It is biosphere because Biosphere refers to the area of the Earth or part of the ecosystem where living organisms lives , contain biogenic organic matter and it's also include ground and air.

It comprises of the area of water, air and land that support life or survival of living organisms.

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.  

read more on -

b c a d mark me