Page 149 - If Darwin Had Known about DNA

Adnan Oktar

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lation, which occupies a very important place in human development.
Different regions of the genes are switched on and off during the course

of embryonic growth; thus a brain cell looks different from a liver or
muscle cell and performs entirely different functions. As you now
know, the type of cell is determined according to the varieties and
quantity of proteins it produces. Cells become liver cells, stomach cells,
skin or muscle cells because of the proteins they manufacture. And the
genes tell the cells which proteins to produce. This production takes

place as a result of some genes being switched on and others off. Liver
cells, for example, produce different proteins with different properties
by switching on different sets of genes than do skin cells.
Since the genes tell the cells which proteins to produce, any cell
lacking genes could survive for only a short time, because it needs to be
given instructions on what proteins to manufacture. Otherwise, the
supply of fresh proteins would shortly come to an end, and the cell
would be unable to perform vital functions. At certain times, for exam-
ple, the genes instruct the cells to manufacture the special proteins that

permit blood to clot. Flawed genes, however, cannot manage this, re-
sulting in hemophilia, a disorder of the blood-clotting mechanism.
The human body needs to manufacture some proteins throughout
its entire life, and others solely at times of need. For that reason, genes
regulate every cell so that it produces the correct amount of protein at
the exact times required. In the developing embryo, for example, sever-
al proteins are necessary in a very short space of time. The proteins pro-

duced by any specific cell depend on where in the embryo it lies, are,
the developmental age of the embryo, and the instructions it receives
from its own genes and from other cells. But scientists cannot say how
the cell knows when to ignore which part of the enormous blueprint it
possesses, and when. How are the genetic "files" for every feature and