Describe how scientists use technology to determine if genes are 'turned on' or 'turned off'.

Other regulators respond to changing environmental signals, such as the amount of protein or trace metals in the diet. Scientists are using the knowledge about gene regulation plus new cloning tools to investigate the physiological effects of switching specific genes on or off in living animals.

The process of determination is "Gene Regulation" and it is process of turning genes on and off. ensures that the appropriate genes are expressed at the proper times. Cell which expresses, or turns on is known as "Turned on" cell whereas which are repressed, is "Turned off"

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