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Discussion Starter · #1 ·
Which of the following is used as a metabolic energy source by erythrocytes after an overnight fast?

(A) Free fatty acids
(B) Glucose
(C) β-Hydroxybutyrate
(D) Pyruvate
(E) Triglycerides
 

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Red Blood Cells depend exclusively on anaerobic glycolysis to produce energy (i.e. they have no mitochondria), irrespective of what the conditions are (glucose sufficiency after a meal or glucose depletion during fasting). Thus answer B is correct and answers A & E are not correct.

On the contrary, neurons may also use ketoacids as fuel, but this is not the case here (answers C & D are incorrect, although they seem very tempting).
 

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Red Blood Cells depend exclusively on anaerobic glycolysis to produce energy (i.e. they have no mitochondria), irrespective of what the conditions are (glucose sufficiency after a meal or glucose depletion during fasting). Thus answer B is correct and answers A & E are not correct.

On the contrary, neurons may also use ketoacids as fuel, but this is not the case here (answers C & D are incorrect, although they seem very tempting).
Simple concept but you nailed it in the head here for me. Thanks
 

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Discussion Starter · #5 ·
yes B

Dr. ath's explanation was good enough. when come across this question no need to look at other choices. RBCs must and always use Glucose only. neurons (brain cells) can resort to ketones during depletion but the RBCs continue to use glucose.
 

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i also thot abt glucose just now wen i saw!!!:D
 
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