Page 151 - The Miracle in the Cell Membrane

Harun Yahya (Adnan Oktar)

A potassium ion
combined with
water molecules Closed Open

Ion
binding
region
Neutralizing
particle
(a) Channels' ion selectivity (b) Gate formation in the channel

These diagrams show how the
Cell
closed voltage ion channels select membrane
the potassium ion. (a) 1- Negative
charges at the entrance to the chan-
nel attract positive charges. 2- The Neutralizing
diameter of the channel restricts the particle
amount of ions that will pass
(c) Neutralization of the channel
through. 3- After the ions have been
selected they separate from the
water molecules. (b) When the electrical state of the membrane changes, the
structure of the channel changes, and the channel gate opens. (c) After ion pas-
sage has taken place, the channel is again closed by a neutralizing particle.

The Sodium-Potassium Pump
In addi tion, pro tein pumps requir ing ener gy are also
used to trans port ions. One of the best known pump ing
sys tems is the sodi um-potas si um type. The pro tein con -
sti tut ing the chan nel in the cell mem brane uses up a third
of the cell's total ener gy pro duc tion. This pro tein works
non-stop, day and night, pump ing sodi um ions to the
out side, while attract ing potas si um ions to replace them.
During each pump ing proc ess, three sodi um ions (Na+)
are sent out side the cell, and two potas si um ions (K+)

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