What is the primary purpose of gel electrophoresis?

To separate large molecules like DNA fragments based on their size.

In gel electrophoresis, DNA molecules move towards which electrode and why?

DNA molecules move towards the positively charged anode because of the negatively charged phosphate groups in their backbone.

The gel acts as a sieving matrix, allowing smaller DNA molecules to travel faster and farther than larger ones.

Shorter molecules travel farther than longer molecules.

A DNA-binding dye that fluoresces under UV light is added to visualize the DNA bands.

Grade 14 · Science · 50 min

I can prepare an agarose gel for electrophoresis.

Professor Dave Explains · 5:17

Gel Electrophoresis

3 key concepts

1
Gel electrophoresis is a method used to separate large molecules like segments of DNA.
2
In gel electrophoresis, smaller DNA molecules travel greater distances through the gel, while larger ones travel shorter distances.
3
After separation, a DNA-binding dye is added, which glows a fluorescent pink in UV light, allowing visualization of DNA bands.

12 questions · Multiple choice & Short answer

Quick comprehension check

“Describe the composition of the gel used in gel electrophoresis and its purpose in the separation process.”

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