Answer:
Extension
Explanation:
Polymerase chain reaction is given by Kary Mullis and it contains three steps denaturation, annealing, and extension. In denaturation, the temperature is raised to 96° c so that the DNA can denature.
In annealing, the temperature gets reduced to 55°c so that the primer can bind to the complementary sequence. In extension, Taq polymerase is used to extend the new strand.
This enzyme is isolated from thermophilic bacteria and the temperature here is raised to 72°c so that the enzyme can extend the primer and make the complementary strand. So the right answer is extension.
The answer is a person removes their hand after touching a hot stove and a person turns their head toward the source of loud noise.
External stimuli are factors outside of the body that is taken in by receptors and will lead to a response. Examples of external stimuli include temperature changes, vision, hearing, tasting, smelling, and even sunlight for plants.
Learn more about External stimuli here:
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