Question

how many atp molecules are produced by the aerobic oxidation of one molecule of glucose?

Answer 1

Hello mate.

Thanks for asking this question.

Your answer is =>

In Aerobic Respiration , there totally 38 ATP molecules produced. Now lets find At wich steps we get them ;

[1] In $\underline{Glycolysis}$ =>

in Glycolysis , total 4 ATP are formed by substrate level phosphorylation but 2 ATP are also consumed during the conversion of :-

1) Glucose into Glucose-6-phosphate and

2) Fructose-6-phosphate to Fructose-1,6- bisPhosphate.

now , we get a net gain of (4-2) => 2 ATP .

so in Glycolysis , total 2 ATP are formed by substrate level phosphorylation.

also , during Glycolysis , 2 molecules of $NADH_2$ are also formed.

by using ETS , we obtain (2×3) = 6 ATP molecules.

so ,

During Glycolysis , total net gain of ATP is(2+6) = $\boxed{8 \:ATP}$ molecules .

[2] $\underline{Link \:Reaction}$ =>

during link reaction ;

pyruvate is converted into Acetyl CO-A forming 2 molecules of $NADH_2$.

by using ETS ,
we obtain (2×3) = 6 ATP molecules.

in link reaction ,

we get $\boxed{6\:ATP}$ molecules.

[3] $Kreb's \:Cycle$ =>

During Kreb's Cycle , 2 molecules of $NADH_2$ are obtained at following steps =>

1) isoCitrate -----> Oxallo Acetate.

2) $\alpha$-keto gluterate----> succinyl CoA.

3) Malate ------> Oxalo acetate.

so there are totally 3 steps where we get 2 molecules of $NADH_2$.

so , by using ETS , we get ,

=> (2×3)×3 = 18 ATP.

also , we get 2 molecules of $FADH_2$ from succinate.

so , by using ETS. , we get (2×2) = 4 ATP.

Also , we get 2 molecules of GTP/ATP from Succinyl CoA.

so , we concluded that , net gain of ATP during Kreb's Cycle =>

18 + 4 + 2 = $\boxed{24 ATP.}$

now if we add all the ATP gains during Glycolysis , Link Reaction and Krebs cycle =>

8 + 6 + 24 = $\underline{\huge{\mathbb{\bf{38\:ATP.}}}}$



$\underline{\huge{\mathbb{\bf{B}e}\mathbb{\bf{B}rainly}}}$