The organism shown is a free-living one that is anchored to the bottom of ponds and streams during the first part if its life cycle. what is the common name of the group to which this organism belongs? a. comb jellies b. arthropods c. echinoderms d. cnidarians

cnidarians

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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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