Final answer:
Ethidium bromide is not included in the gel loading dye used in gel electrophoresis.
Step-by-step explanation:
The gel loading dye is a solution used in gel electrophoresis to make it easier to load samples into the gel. It typically contains several components, including ethidium bromide, xylene cyanol FF, glycerol, and bromophenol blue. However, ethidium bromide is NOT included in the gel loading dye. Ethidium bromide is a nucleic acid stain that is added separately to visualize DNA in the gel.