[Animation] - Combination of Switches: the Lac Operon

Is the lac operon like a light bulb connected to two switches?

The lac operon is controlled by two switches one triggered by the presence of glucose and the other by the presence of lactose. When a light bulb is controlled by two switches there are four possible orientations: switch A and switch B both up, switch A and switch B both down, switch A up and switch B down, or switch A down and switch B up. The first two of these orientations will result in the light being on and the last two orientations will result in the light being off. In contrast only one orientation of switches will turn on the lac operon - both switches must be on.

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