band obove the ladder - (Dec/17/2014 )

why the band above the ladder?why the other have no band?

what did you do?

what are we looking at (don't say "an agarose gel")?

It looks like there might be some contamination in the marker.  A band toward the top of the lane like that indicates a large DNA size.  I would run it again with a fresh marker not previously used.

That band is a large DNA. Not a contamination though.

Ladders are usually made by cutting a large DNA with specific restriction enzymes, so if there was some undigested DNA left over (and sometimes it is deliberately partially digested, to get the desired pattern from a tandem repeat large DNA), it shows up as that. 

I have never put an ant in the agarose gel well. I wish at least she had run