Question

Which of the following statements best describes a primary mechanism by which the energy released in ATP hydrolysis is used directly to drive endergonic chemical reactions in a cel? a.Free energy is released as heat which speeds up the rate of endergonic reactions b.Binding of ATP to an enzyme active site converts an endergonic reaction to an exergonic reaction c.The released phosphate is used to form phosphorylated intermediates that are more reactive than the original unphosphorylated substrate d.The phosphate is combined with ADP to regenerate ATP.

Answer 1

The correct answer is c. The released phosphate is used to form phosphorylated intermediates that are more reactive than the original unphosphorylated substrate.

Step-by-step explanation:

In cells, ATP hydrolysis releases free energy, which is used to drive endergonic chemical reactions that require energy input. The released phosphate group is transferred to specific substrates to form phosphorylated intermediates, which are more reactive than the original unphosphorylated substrate.

This increase in reactivity allows the substrates to undergo chemical reactions that would not be possible in the absence of the phosphate group. The transfer of the phosphate group to the substrate is catalyzed by enzymes known as kinases. This mechanism of using the released phosphate to drive endergonic reactions is known as substrate-level phosphorylation.