Question

The major advantage of coupling biochemical reactions is:

	a.	to increase the energy release from the hydrolysis of ATP
	b.	to release energy from ATP hydrolysis to the environment
	c.	to take advantage of coenzymes such as NADH
	d.	to drive an unfavorable reaction by concerted transfer of energy from a favorable reaction

Answer 1

The answer is

d ) to drive an unfavorable reaction by concerted transfer of energy from a

favorable reaction.

Cells use a strategy called reaction coupling. That is  an energetically favourable reaction (like ATP hydrolysis that release energy/exergonic) is directly coupled with an energetically unfavourable (endergonic) reaction.

In simple way it can be explained that exergonic and endergonic reactions are always coupled.

for example glycolytic reactions. Glucose to glucose 6 phosphate (endergonic) is coupled with ATP to ADP+Pi (exergonic)