Electrophoresis is primarily used for which purpose?

• A. To measure pH levels.
• B. To separate macromolecules based on size and charge.
• C. To identify chemical compounds.
• D. To amplify DNA sequences.

Answer: (B)

Electrophoresis is primarily utilized to separate macromolecules, such as proteins and nucleic acids, based on their size and charge. The process involves applying an electric field to a gel matrix, which causes the macromolecules to migrate toward the electrodes. Smaller molecules or those with a greater charge will move faster than larger or less charged ones, allowing for their separation. This technique is especially valuable in various biological and biochemical applications, such as analyzing DNA fragments, protein purification, and genetic fingerprinting.

In contrast, measuring pH levels involves different analytical methods, while the identification of chemical compounds typically relies on techniques like mass spectrometry or chromatography. Amplifying DNA sequences is primarily accomplished through polymerase chain reaction (PCR), not electrophoresis. These distinctions highlight the specific role of electrophoresis in molecular biology and biochemistry.