How are molecules separated in electrophoresis? Right Ans - charge, size,
shape
Why is electrophoresis useful? Right Ans - separates charged biomolecules
such as DNA, RNA and proteins.
In this process, DNA molecules migrate to the "+" pole as an electrical current
passes through the gel. DNA molecules of different lengths separate with the
shorter fragments moving faster through the gel compared to the larger
fragments. In addition, the "shape" (linear or circular) of the DNA molecule
will affect the migration of the DNA molecule.
What is the gel made up of? Right Ans - dissolving agarose powder in
boiling buffer solution. The solution is then cooled and poured into a gel tray
where it solidifies.
The tray is submerged in a buffer-filled electrophoresis apparatus.
How are samples prepared for electrophoresis ? Right Ans - by mixing
them with components that will give the mixture density. These samples can
then be loaded with a micro-pipet into wells that were created in the gel by a
comb during casting. The dense samples sink through the buffer and remain in
the wells.
DNA charge Right Ans - DNA has a strong negative charge. because of this,
it migrates through the gel towards the positive electrode during
electrophoresis
Why is power applied to the electrophoresis apparatus? Right Ans -
Molecules having a net negative charge migrate towards the positive electrode
(anode) while net positively charged molecules migrate towards the negative
electrode (cathode). Within a range, the higher the applied voltage, the faster
the samples migrate.