Page 161 - The Miracle in the Cell

HARUN YAHYA

PREPARATORY
CONVERSIONS
Pyruvic acid
NAC + Co Enzyme A
CO 2

Acetyl CoA
Krebs cycle
2
Figure 8.6 H O
During the second stage of the
aerobic respiration pathway, Co enzyme A
pyruvate enters the mitochondri-
on, where it is broken down Oxaloacetate Citrate
completely. Carbon dioxide and
water are obtained from the Malate Isocitrate
resulting carbon and oxygen
atoms-the source of the carbon
dioxide breathed out through the x-ketoglutarate
lungs. Fumarate
As the diagram shows, before
entering the Krebs cycle, the
pyruvate is completely converted
into acetyl coenzyme A, which Succinate
then enters the Krebs cycle and Succinyl CoA
combines with oxaloacetate (The Co
Krebs cycle got its name from the Enzyme A
scientist who worked on it in the
1930s). The Krebs cycle has three
functions: The first is to obtain
H+ and electrons to transfer to
coenzymes such as NAD and
FAD. The second is production
of ATP by phosphorylation. And
the third is to convert the many
different substances in the center
of the cycle, obtained after many
steps by many different
enzymes, back into oxaloacetate.
If this reconversion was not
done, and there is only a limited
amount of oxaloacetate in the
cell, respiration would soon stop.
But because of the extraordinary measures taken by God, oxaloacetate is always
regenerated. The incredible reactions that take place in the second step produce
only two ATPs. But many of the coenzymes, H+ ions and electrons produced in
this step are used in the third and final stage of respiration.

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