Electrophoretic techniques that distinguish DNA fragments by size are essential in forensics and in the mapping of restriction sites within genes. The Analysis of Precut Lambda DNA Kit demonstrates basic procedures and principles of DNA gel electrophoresis, including agarose gel casting, sample loading, size-based separation of DNA fragments, DNA staining, and graphic analysis. This activity provides in-depth explanations about how restriction enzymes cut DNA and how electrophoresis can be used to separate and visualize DNA fragments.
Features and Benefits
- Aligns with AP Biology Lab 9
With this kit, students are able to:
- Study DNA restriction enzyme function
- Use electrophoresis to separate DNA fragments
- Construct standard curves from their data and make precise determinations of DNA fragment sizes
Applications and Uses
By visualizing the effect of three restriction enzymes on four identical samples of double-stranded lambda virus DNA, students learn that different restriction enzymes recognize and cut different DNA sequences. Optional extension exercises guide students through the procedure of DNA fragment size determination by constructing a standard curve using their own gel data. Students can then use the standard curve to determine the sizes of the various DNA fragments in their samples.
- Two–session laboratory activity, 45 min per session
- Provides sufficient materials for eight student workstations, up to four students per workstation