What are two reasons why terrestrial plants formed closer to the sun after the supernova event that initiated the formation of the solar system

- They are made of denser objects, which can condense at relatively high temperatures;

- They are made of heavier elements, which have a stronger gravitational attraction to the Sun;

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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i think its control and coordinate because im pretty sure thats what tissue does and the joints are what control movement and then your skeletal/ bones provides portection. hope that .