Page 100 - The Miracle in the Cell Membrane

o sub stance that enters the blood stream for
any rea son can enter the cell as soon as it
reach es the cell mem brane. It is met in dif -
fer ent ways, depend ing on its size, its
chem i cal prop er ties, and wheth er it is ben e fi cial or harm -
ful. Before it enters the cell, any sub stance is sub ject ed to
strict checks, just as at the cus toms at a coun try's bor ders.
If it is decid ed that a for eign sub stance poses a threat, it
is not grant ed admit tance. Depending on their iden ti ty,
how e ver, the entry and depar ture of some sub stan ces has
been facil i tat ed, just as with cit i zens return ing to their
home coun tries. These sub stan ces can enter and leave the
cell with ease, with out being sub ject ed to secu ri ty checks.
Some sub stan ces even enjoy a spe cial right of entry, like
cit i zens bear ing spe cial pass ports. In short, var i ous meas -
ures are imposed on sub stan ces enter ing the cell mem -
brane.
In order for a sub stance to pass through the cell mem -
brane—to com bine with the sub stance of the mem -
brane—, it needs to be fat-sol u ble. No mat ter how hard
you try, you can never mix liquefied fat with water. In
the same way, any sub stance that can not be dis solved in
fat can never mix with the cell mem brane. To per mit sub -

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