Communication between neurons occurs from contact between the two neurons. when the intensity of the action potential increases past a threshold. when action potentials trigger the release of neurotransmitters. because of the all-or-none response. through the selective permeability of the axon.

The correct answer is - when action potentials trigger the release of neurotransmitters.

Explanation:

Communication between neurons takes place by signaling that can be either chemical signaling or electrical signals. Communication between neurons occurs at very small gaps known as synapses.

These synapses have two specialized cells that help two neurons communicate by one to another to allow for chemical transmission. The chemical that isreleased due to the stimulation of the action potential in order to communicate the neurons are known as neurotransmitters that allow for transmission.

explanation:

b,bacteria convert nitrates

into nitrogen gas.

d,plants and animals take in

and use nitrogen compounds.

e,bacteria break down waste    

products and return nitrogen  

to the soil.

a,bacteria convert atmospheric

nitrogen to ammonia.

c,bacteria convert ammonia

to nitrites and nitrates.

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