Which of the following statements concerning biotin and gluconeogenesis is false ? A) Biotin is used to add CO₂ to certain intermediates in gluconeogenesis. B) CO₂ is incorporated into the glucose product. C) Biotin is capable of binding covalently to CO₂. D) Biotin helps synthesize an important precursor of phosphoenolpyruvate. E) ATP hydrolysis is required to attach CO₂ to biotin.

Question

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Biotin functions as a coenzyme in carboxylation reactions, such as the conversion of pyruvate to oxaloacetate, an important step in gluconeogenesis. However, CO₂ (a placeholder for a chemical group) is not incorporated into the glucose product itself. Glucose is produced through a series of enzymatic reactions that modify the carbon skeletons of substrates like pyruvate, lactate, glycerol, and amino acids, but the specific chemical groups added by biotin (e.g., carboxyl groups in carboxylation reactions) are not part of the final glucose molecule.

Which of the Following Statements Concerning Biotin and Gluconeogenesis Is