miniPCR bio
TM
Dye Electrophoresis Lab: Molecular Rainbow - Instructor's and Student's Guide
Version: 1.0 - Release: April 2022 - © 2022 by miniPCR bio™
Student's Guide
P./10
When scientists discuss molecules separating in a gel, they talk about bands moving in lanes. Let's
take a closer look at what these two terms mean.
Green Green
Blue
Purple
Red
Lane
2
Lane
3
Lane
4
Lane
Charged molecules that are put in a well will move towards the electrode that has an opposite
charge. As they move through the gel, they travel in a straight line. Like runners on a track, when
we talk about the molecules moving through a gel, we talk about them moving in lanes.
There are usually billions of molecules in each
well of the gel. As the molecules move towards
an electrode with the opposite charge, all of the
molecules that have the same charge and size
will move through the gel in the same direction
and at the same speed. This group of molecules
moving together will stay in about the same
shape as the well they started in. When you look
at the gel, the group of molecules will look like
a small horizontal line on the gel. We call these
lines bands.
In Lane 4, there are two bands: a red band
made of billions of red molecules and a purple
band made of billions of purple molecules. Both
of these bands started in the well in Lane 4,
but as the molecules moved through the gel
the two bands separated because the red and
purple molecules are different sizes and traveled
through the gel at different speeds.
Bands
Review
-
1. What causes molecules to move through the gel during gel electrophoresis?
2. What role does the gel play in gel electrophoresis?
1
2
