The following is a food chain that exists in a desert ecosystem. Cacti--> Foxes--> Eagle Owl
Which of the following factors is most likely to impact the carrying capacity of the
cactus populations?
An increase in the number of foxes eating the cacti in the area.
An increase in the amount of rain.
A decrease in the number of foxes eating the cacti in the area.
All of the above will impact the carrying capacity of the cactus population

All of the above will impact the carrying capacity of the cactus population.

Foxes can increase and decrease the cactus population, and since cactus is plant, they also need rain to flourish. So all of the above applies.

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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