DONT KNOW WHAT TO DO PLEASE HELP Design your own experiment to test how your body changes during exercise. You may develop this new experiment to test the changes in heart rate, breathing rate, or any
other parameter occurring during exercise.
Part A
First, formulate a question to answer through scientific investigation. Keep in mind
that you should be able to answer your question with measurable data. Write your
question here.

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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any abiotic or biotic factor in an ecosystem that causes a population's size to slow or decrease is a limiting factor.

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