Page 186 - The Miracle in the Cell Membrane

The Miracle in the Cell Membrane

a spe cif ic shape will open a lock, each recep tor func tions
only when it binds to a mol e cule (ligand) of the right
shape.
These recep tors select the dif fer ent hor mones to which
they need to bind them selves, never mak ing a mis take.
However, there is no need of trial and error for the right
lock and key to final ly come togeth er. Bear in mind that a
sin gle error could have fatal con se quen ces, and you can
bet ter appre ci ate the per fect order in your body. This order
of our Lord's is revealed in a verse from the Qur'an:
. . . He cre at ed every thing and deter mined it most exact -
ly. (Surat al-Furqan, 2)

Hormones' Effect on the Receptors
A hor mone cre ates its effect by acti vat ing tar get recep -
tors in the cell mem brane. When hor mones attach them -
selves to these recep tors, they cause chan ges in the recep -
tor's pro tein struc ture. Some hor mones have open ing and
clos ing effects, sim i lar to the ion chan nels in the cell mem -
brane. For exam ple, they cause sodi um and potas si um
chan nels to open and close. In this way, these ions alter the
poten tial of mus cle cell mem branes and lead to a stim u lat -
ing effect in some cells, and a calm ing effect in oth ers.

The Speed of Signal Transmission
The speed at which hor mones' com plex sys tem works
is also aston ish ing. The mes sen ger mol e cu le's reach ing the
cell, its attach ment to the cell mem bra ne's anten na, ini ti a -
tion of the chem i cal reac tion form ing the bond between the
hor mone and anten na, trans fer ence of the hor mo nal mes -

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