DNA

MATERIALS:

     bar codes 

ADVANCED PREPARATION:

     Cut out bar codes from products. Each suspect receives a different bar code, which represents his/her DNA. Make up a sheet of one of the bar codes and identify as "DNA found at crime scene."

PROCEDURE:

1. Look at the DNA codes from the suspects.
2. Compare them to the DNA code that was found at the crime scene.

BACKGROUND:

     DNA analysis is a complicated process, which involves several steps. The DNA is removed from the cell nucleus and then the DNA strands are separated from the rest of the cell parts and chopped into smaller pieces. The human DNA pieces are combined with radioactive DNA. The scientist will be able to track the pieces of human DNA later. The DNA pieces are separated from one another into bands according to size, using gel electrophoresis. This process is similar to chromatography. X rays are taken of the separated DNA pieces to record the individual’s DNA profile.