[NO LINKS] John and Emily were experimenting with the effects of road salt on plant growth. To do this, they watered plants daily with the same amount of salt water. They could best improve their experiment by Question 16 options:

increasing the amount of salt added to the water each day

cooling the salt water before watering the plants

adding food color to see how far the salt penetrates the plants

watering half the plants with pure water and half with salt water

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 it’s c but i might be wrong. if i am let me know! have a good rest of your day as well!

the glands which are associated with each description is given below: