Answer: (1) boiling point.
Explanation: Gel electrophoresis is a technique used to separate DNA fragments (or other macromolecules, such as RNA and proteins) based on their size and charge. Electrophoresis involves running a current through a gel containing the molecules of interest. The molecules will move faster or slower based on their size and electric charge. Smaller molecules move faster and migrate farther than larger ones because they can pass through the pores of the gel more easily. This phenomenon is called sieving. Similarly, molecules with a higher charge will move faster and migrate farther than molecules with a lower charge because they are more attracted to the opposite electrode.
Boiling point is not a characteristic that affects the separation of molecules during gel electrophoresis because it is not related to the size or charge of the molecules. Boiling point is the temperature at which a liquid becomes a gas, which depends on factors such as intermolecular forces, pressure, and molecular weight. Boiling point does not affect how fast or far a molecule moves in an electric field. Therefore, it is not used to separate molecules during gel electrophoresis.
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