are the chemicals that facilitate the flow of electrical impulses from one neuron to the next across nerve synapses; and the presence or absence of both serotonin and noradrenaline have been linked to aggressive behavior in human beings.

Neurotransmitters

Explanation:

Neurotransmitters are chemicals synthesized in neuron and bloodstream and move to distal sites where they functions by transmitting signals across a synaptic junction, from one neuron to another.

affects the water bodies: excessive use of fertilizers causes eutrophication. the fertilizers which are used on plants affect the quality of land on which it is used, further causing erosion of soil. the fertilizers used on plants contain harmful chemical fumes which affect the environment.

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