The first step of glycolysis is phosphorylating glucose to make glucose 6-phosphate as shown below. Which of the following statements about this reaction is TRUE? Glucose + P_i → glucose 6-phosphate + H₂O ΔG = + 3.3 kcal/mol A) This reaction releases energy. B) This reaction is spontaneous. C) This reaction cannot occur in the body. D) This reaction must be coupled to another reaction to occur. E) An enzyme is required to provide the energy for this reaction.

Question

Quizplus · Accepted Answer

This reaction requires an input of energy in the form of ATP to form glucose 6-phosphate. Therefore, it must be coupled with the hydrolysis of ATP to ADP and Pi in order for the reaction to occur. This makes choice D the correct answer. Choices A, B, and E are incorrect because they imply energy release, spontaneity, or an enzyme providing energy, which are not true for this reaction. Choice C is incorrect because this reaction does occur in the body as the first step of glycolysis.

The First Step of Glycolysis Is Phosphorylating Glucose to Make