The first point along the graph where a response above zero (or above the control response) is reached is usually referred to as a threshold-dose. For most beneficial or recreational drugs, the desired effects are found at doses slightly greater than the threshold dose. At higher doses, undesired side effects appear and grow stronger as the dose increases. The more potent a particular substance is, the steeper this curve will be. In quantitative situations, the Y-axis often is designated by percentages, which refer to the percentage of exposed individuals registering a standard response (which may be death, as in LD). Such a curve is referred to as a quantal dose-response curve, distinguishing it from a graded dose-response curve, where response is continuous (either measured, or by judgment).\n\nThe threshold on a dose-response curve is the?
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To answer this question, we should know that: The first point along the graph where a response above zero (or above the control response) is reached is usually referred to as a threshold-dose.
So, the answer is The first point along the graph where a response above zero ( or above the control response ) is reached.
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