First, they may produce direct and relatively short-lived effects, such as stimulation of the isolated uterus or relaxation of the isolated tracheal chain preparation.
Secondly, in doses too low to produce a direct effect, they may produce a long-term potentiation of the effects of other stimulants.
Answer:
Electronegativity is a measure of an atom's ability to attract shared electrons to itself. On the periodic table, electronegativity generally increases as you move from left to right across a period and decreases as you move down a group.
Explanation:
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