The alarm reaction to danger that is triggered by anxiety primarily involves the nervous system.

Sympathetic

The alarm reaction to danger that is triggered by anxiety primarily involves the sympathetic nervous system

Explanation:

The sympathetic nervous system (SNS) primarily stimulates many parts of the body for action in times of danger or emergency situations.

During this process, a hormone known as adrenaline (the emergency hormone) would be released, and effects such as sweating, increased heartbeat, raised blood pressure will follow.

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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