Why can't glucose spontaneously become glucose-6-phosphate?

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Multiple Choice

Why can't glucose spontaneously become glucose-6-phosphate?

Phosphorylation of glucose requires energy input. Attaching a phosphate group to glucose is an endergonic step unless energy is supplied by another reaction. In cells, hexokinase couples this phosphate transfer to ATP hydrolysis, producing glucose-6-phosphate and ADP. The energy released from breaking the high-energy phosphate bonds in ATP drives the overall reaction forward, so glucose won’t convert to glucose-6-phosphate spontaneously without that energy source. That’s why this step is described as requiring energy input and being thermodynamically unfavorable on its own. The other statements don’t fit: there is an enzyme to catalyze the reaction, it doesn’t release energy on its own, and it does not happen spontaneously without energy input.

Phosphorylation of glucose requires energy input. Attaching a phosphate group to glucose is an endergonic step unless energy is supplied by another reaction. In cells, hexokinase couples this phosphate transfer to ATP hydrolysis, producing glucose-6-phosphate and ADP. The energy released from breaking the high-energy phosphate bonds in ATP drives the overall reaction forward, so glucose won’t convert to glucose-6-phosphate spontaneously without that energy source. That’s why this step is described as requiring energy input and being thermodynamically unfavorable on its own. The other statements don’t fit: there is an enzyme to catalyze the reaction, it doesn’t release energy on its own, and it does not happen spontaneously without energy input.

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