If someone does not get sufficient calories for quick energy what is most likely the next response the body will take?

Tiredness. The person feels tired

Explanation:

If you eat too little, you may not obtain as much energy as you need. This will make you feel tired

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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organ system-an organ system is a group of organs that work together to perform one or more functions. each does a particular job in the body, and is made up of certain tissues.