Air, not water, is the compound of life true or false

False. Air is a mixture not a compound which automatically makes this false! There is also not a single compound of life but rather several that are referred to as the compounds of life.

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 tunica intima also called tunica interna, consists of elastic fibers,connective tissue and smooth muscle cells;