Final answer:
The false statement is D: The phosphorylation of Y is endergonic.
Step-by-step explanation:
The false statement is D: The phosphorylation of Y is endergonic.
According to the information provided, ATP hydrolysis is an exergonic reaction, releasing ~7 Kcal/mole of energy. This means that the phosphorylation of Y, which involves the transfer of a phosphate group from ATP to Y, is an exergonic reaction as well. Exergonic reactions release energy.
The overall reaction (1 + 2) is also exergonic because the release of energy from the hydrolysis of ATP (reaction 1) is greater than the energy required for the phosphorylation of Y (reaction 2). Therefore, statement C is true.