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A person eats cookies made with coconut oil. The predominant fatty acid in the triglycerides contained in the coconut oil is lauric acid, which is a saturated 12-carbon fatty acid. Starting with free lauric acid within the mitochondria, what is the net energy yield in high-energy phosphate bonds from each molecule of lauric acid?
A. 83
B. 85
C. 95
D. 97
E. 110
D 97 ATP . 12 C yield 6 acetyl coA which makes 72 ATP
5 NADH 15 ATP
5 FAD 10ATP
is it like that????
D. 95

From the 12C fatty acid we end up getting 6 molecules of Acetyl Co A. This produces a nett of 23 ATP. From each molecule of Acetyl co A, each turn of beta oxidation produces 12ATP.

Therefore.. From oxidation 6x12=72 ATP
Prior to oxidation to produce ACetyl Co A= 25 ATP

Total is 95 ATP. or so i think. Where is this question from biochem2?
DDD?
thats make 97 lucid
sorry, my mistake, i think the nett production of ATP from breakdown for lauric acis bonds is only 23 ATP . some ATP is used for the conversion of FA to FA CoA by FA Co Synthetase right?
The correct answer is C.Here is the calculation you need to perform.

Activation of the laurate requires two high-energy phosphate bonds as ATP is converted to AMP. The 12 carbon lauryl CoA is then split 5 times to produce 6 acetyl CoAs, and 5 ATPs (obtained from 1 FADH2 and 1 NADH), that are produced by each β-oxidation cycle. The resulting 6 acetyl CoA each produce 12 ATP equivalents (one is GTP, which is converted to ATP) when processed by the citric acid cycle.
u were right lucid interval. this is from kaplan q bank. i was clueless abt it. ty for the explanaiton.
i understand that 12C produces 6 acetyl co A and 72 ATPs. can u explain rest of the part.thnx
For Beta Oxidation to begin the fatty acid must be converted to its corresponding Fatty Acyl Co A by the enzyme Fatty Aceyl Co A synthetase. This reaction requires the conversion of ATP to AMP utilizing 2 high energy bonds.

hence you have to subtract these 2 from the gross production of ATP which is 97 (from 6 actely co and 5 NADH and % FAHD2)

hence 97-2= 95
ok thnx lucid,thats how i ended up makin 97.thnx