Expert: Walter Hintz - 4/5/2006

Question
how does DNA hold information?

Answer
I have a whole lecture on this sarah but I will simply summerize things and if you have a question get back to me.
 DNA represents a code and first think about what a code is.  A code uses symbols to transmit information and information is nonmaterial.  Look at this bit of information.  STOP   stop  Both give you informatuion but is it the size of the letters? No, it is the arrangement of the ink. Secondly it makes no differenc e how big my letters are the information is the same so size is immaterial also.  What is the code here? The letters of the alphabet.
 What is the DNA code?  There are four symbols (chemical compounds) in the code. We call them A,T,G and C.  Now you can arrange these four symbols in different sequences.  DNA is made up of strands of these four symbols in thousands and the sequence is the code. Example:
    AGCGTTAAGC is one sequence
    GCTTAGCTTG is another
 A code must be read  and DNA code is read when a particular protein is made in the cell.  One sequence brings about hemoglobin for example and another insulin.  If only one symbol is changed the sequence is different and the code is read differently.  In cystic fibrosis there is an error in the sequence and the disease appears.
 This remarkable code is the secret of life.
 Get back if you have any questions