Page 24 - The Secrets of the DNA

two new DNAmolecules are produced. In every phase of the operation, expert
proteins called "enzymes" that function like advanced robots take part. Though
it seems simple at first sight, the intermediary processes taking place through-
out this operation are so many and so complicated that to describe the whole
event in detail would take pages.
The new DNAmolecules that emerge during replication are checked repeat-
edly by inspector enzymes. If there is any mistake done - which can be quite
vital, it is immediately identified and corrected. The erroneous code is removed
and replaced by the correct one. All these processes take place at such a daz-
zling speed that while 3.000 base pairs are produced in a minute, on the other
hand, all these pairs are checked repeatedly by the enzymes in charge and the
necessary amendments are made.
In the newly produced DNAmolecule, more mistakes can be done than nor-
mal as a result of external factors. In this case, the ribosomes in the cell start to
produce DNA repair enzymes upon the order given by DNA. Thus, as DNA
protects itself, it also guarantees the preservation of the generation.
The cells are born, they reproduce and die just like human beings. Yet the life
spans of cells are much shorter than the life of the human they constitute. For
instance, the majority of the cells that used to make up your body six months

THE SECRETS OF DNA
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