Which of the following correctly describes a nucleus? All cells have a nucleus
The nucleus is where mitosis occurs
The nucleus gives the cell energy
The nucleus is where plants make their own food

protein synthesis is an example of feedback mechanism which in homeostasis

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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mammal

explanation: