Question

Look up information for the ladder you will be using (Lambda-Phage viral DNA digested with HinDIII). Save this information and also take a snapshot of the ladder (include here) with corresponding basepairs. This ladder would have been/was prepared for you.

Be observant of the band distribution (are they evenly spaced? are their distinctive bands? any close together? These observations will be important for identifying the size of the bands YOU will see on your own gel

Answer 1

The above is the bad pattern observed when digesting lamda DNA with Hind - III. The digestion with HInd-III gives rise to number of fragments of the DNA of varying sizes. When these restriction fragments are run through the gel, based on the size of the fragments, they travel at different rates. This results in formation of bands at different regions on the gel. Larger fragments move slowly, so we see the larger fragments near to the region of loading. Smaller fragments move faster and are more near to the positive electrode.

Bands are not evenly distributed. Bands move based on their size, that is why their distribution also is not even. Larger bands with 23130 basepairs are near to the region of loading. Band with 564 base pairs is more near to the positive electrode as it travels faster.

Using the above ladder the size (bps) of the unknown DNA can be understood,