This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Biochemistry
TCA cycle does not take place in 
Select and explain. 
A. Hepatocytes, B. Osteocytes, C. Neuron, D. Erythrocytes
D: Erythrocytes
Answer: D: Erythrocytes 
Explanation: Erythrocytes (RBC) lack mitochondria (so TCA cycle enzymes) and completely rely on glucose as their metabolic fuel. They metabolize it by anaerobic glycolysis.