Aarthi,
Two buffer chambers are used for the purposes of electrophoresis. The
upper chamber acting as the anode and the lower chamber as the cathode.
The slab gel itself acts as a gate and draws current between the two
chambers promoting the electrophoresis of the DNA fragments. The
average pH of the TBE buffer used in the system is around 7.5 and
formamide promotes the denaturation of DNA molecules from double
stranded to single stranded.
Regards,
Dale