Predict what would happen if a non native beetle began to kill most of the producers

Producers are plants. So, if it started killing all the plants, other native beettles and animals will suffer from hunger, since they wont have food. Even higher members of the foodchain might suffer if their prey start dying.

Depending on what plants their killing, that could also affect the agriculture which in turn affects the evironment since the use of pesticides will be needed.

Hope it helped,

BioTeacher101

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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b a mature ovary of a plant.