Page 78 - Miracles Within the Molecule

HArun yahya

fea ture of hydro gen bonds is their elas tic i ty. Since these bonds are not
as strong as the ester bonds bind ing the nucle ot i des togeth er, they can
eas i ly break in the pres ence of pH dif fer ence, heat or pres sure. The
impor tance of the elas tic i ty in the bonds is this: It is pos si ble for DNA to
be cop ied and for genet ic infor ma tion to be trans mit ted to other cells
only by means of this prop er ty of elas tic i ty.
As you know, DNA needs to rep li cate itself dur ing cell divi sion, so
that each "daugh ter" cell can pos sess its own iden ti cal data bank.
Therefore, imme di ate ly before the cell divides, DNA pro du ces a copy of
itself, first divid ing itself down from the mid dle, like a zip per. In order
to rep li cate itself, the miss ing halves of both sec tions are com plet ed with
mate ri als ready in the cel lu lar envi ron ment, and thus two new DNA
mol e cu les result. By means of the elas tic i ty of the hydro gen bonds,
DNA can split down the mid dle dur ing this proc ess. If this DNA helix
was attached with a dif fer ent type of bond, then the "steps" hold ing the
two halves togeth er would be exceed ing ly hard and inflex i ble and it
would be impos si ble for DNA to divide in two. Either such a divi sion
would not take place at all, or else all the bonds would break when the
two parts of the helix exhib it ed a tend en cy to sep a rate from one anoth -
er, and the mol e cule would break apart. If DNA could not be cop ied, life
would be impos si ble.
The hydro gen and other bonds that form DNA make the helix
exceed ing ly reg u lar. For this rea son, the DNA mol e cule makes reg u lar
turns with out being bound to the chain sequence order. The nucle ot i des
that form DNA, being bound to one anoth er with phos phate bonds, pro -
duce a back bone in which sugar and phos phate sec tions fol low one
anoth er in a series. These bonds, known as cova lent bonds, are extreme -
ly strong. These bonds make the DNA mol e cule high ly sta ble and resist -
ant, even when it has only a sin gle-chain struc ture. While the hydro gen
bonds in the mid dle are able to split away from one anoth er eas i ly, no
break ing occurs in the chains attached to the helix at the side, which are
attached with cova lent bonds. 24

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