AEROBIC
RESPIRATION:
Digestion
and muscle action in human and any other animals,sugar transport through the
plant body-all such activities
depend
absolutely on the high ATP yield of aerobic respiration
Glycolysis is the
first stage of the aerobic pathway two more stages follow.The Pyruvate is
completely degraded and
ATP is
produced in the second stage-the Krebs cycle and few
reactions preceeding it. Also coenzymes NAD+ and FAD pick
up H+ and
electrons that are released during the krebs cycle, and in this way NADH and FADH2 form.In
the third stage,
Electron
transport phosphorylation , the coenzymes give up H+ and
electrons to transport systems.Operation of the transport
system
commonly leads to the formation of 32 ATP, and
this brings the total net yield of the aerobic pathway to 36 ATP.
GLYCOLYSIS:
1)
Glucose, a 6 carbon molecule,gets an ATP-derived phosphate group attached to it
one end,then gets rearranged into
Fructose-6-Phosphate.
2)
Another ATP -derived phosphate group gets attached at the other end, forming fructose-1,6-biphosphate.
3) This
intermediate is split into PGAL and DHAP. Because
each of these molecules is easily converted to the other,we can
say that PGAL have
formed.Beyond this point,each occurs twice for each glucose molecule being
dismantled.
4) The PAGL gives up
2 hydrogen atoms.Both electrons and one proton(H+) of those atoma are picked up
by NAD+ to
form NADH. The PGAL also
combines with inorganic phosphate.The resulting unstable intemidiate donates a
phosphate group to ATP.
5) With
this formation of two ATP, the original energy
investment of two ATP is paid.
6) In the
next two conversions, the intermediate gives up one proton and one OH- ion(which
combine to form water).
The resulting intermediate is phosphoenol
pyruvate(PEP).
7) The
highly unstable PEP readily gives up a phosphate group to ADP,forming ATP.Thus the
net energy yield is
two ATP and two NADH for each
glucose molecule oxidized.
8) The
end product of glycolysis is pyruvate(the
ionized form of pyruvic acid).
AEROBIC
RESPIRATION:
Digestion
and muscle action in human and any other animals,sugar transport through the
plant body-all such activities
depend
absolutely on the high ATP yield of aerobic respiration
Glycolysis is the
first stage of the aerobic pathway two more stages follow.The Pyruvate is
completely degraded and
ATP is
produced in the second stage-the Krebs cycle and few
reactions preceeding it. Also coenzymes NAD+ and FAD pick
up H+ and
electrons that are released during the krebs cycle, and in this way NADH and FADH2 form.In
the third stage,
Electron
transport phosphorylation , the coenzymes give up H+ and
electrons to transport systems.Operation of the transport
system
commonly leads to the formation of 32 ATP, and
this brings the total net yield of the aerobic pathway to 36 ATP.
KREBS
CYCLE:
1) As the
3 carbon puruvate enters the mitochondrion, enzymes split away its COO-
group which departs as CO2.Enzymes
also transfer a proton(H+) and 2 electrons
to NAD+ forming NADH.The 2 carbon molecule remaining
is linked to co-
-enzyme forming the intermediate acetyl-CoA.
2) The 2
carbon molecule becomes attached to oxaloacetate, the
point of entry into the Krebs Cycle, to form
the 6 carbon Citrate.
3)
Citrate is rearranged into the 6-carbon isocitrate, which is stripped of two
hydrogen atoms, with all but one H+ of those atoms being transferred to NAD+ to form NADH. It is
also stripped of a COO- group, this being the
second CO2 to depart.
4) The
resulting intemediate also gives up 2 hydrogen atoms and NADH
forms.And it gives up a COO- group which is the
CO2 to
depart.
5) Enough
energy is released to phosphorylate ADP to from ATP.
6) In the
conversion of succinate to fumarate, 2 hydrogen atoms are transferred to FAD, forming FADH2.
7) In the
last conversion, which regenerate oxaloacetate, 2
hydrogen atoms are stripped away and H+ and two electrons
are transferred to NAD+, forming
the last NADH molecule in the cycle.
