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ATP is metastable (a thermodynamically unstable compound that does not rapidly break down in absence of a catalyst) and is commonly referred to as "free energy currency." Like monetary currency, ATP is used to provide energy in a wide variety of metabolic reactions and is universal among cells. Nevertheless, the energy content of ATP is not significantly different from other nucleoside di- and tri-phosphates. For whatever reason, however, evolution has created an array of enzymes that preferentially bind ATP and use its free energy of hydrolysis to drive endergonic reactions. Hydrolysis of either phosphoanhydride bond in ATP has a of about -31 kJ/mol. Be aware, however, that utilization of that energy to drive endergonic reactions usually does NOT involve hydrolysis of ATP. Instead, ATPbreakdown is usually coupled with a thermodynamically unfavorable reaction. In glycolysis, for example, ATP energy is used to synthesize glucose-6-phosphate from glucose. In this case, the phosphate is transferred directly from ATP to glucose to form glucose-6-phosphate.

Because ATP can transfer a phosphate group, we say that ATP has a high "phosphoryl group transfer potential" rather than calling it a high energy compound. The phosphate anhydride bonds of ATP, ADP, or pyrophosphate have relatively high values. In fact, they are roughly twice as high as the phosphate ester bonds of glucose-6-phosphate or AMP (see also - Figure 3.8). There are, however, cellular compounds with even higher phosphoryl group transfer potentials thanATP. For example, the for breakdown of phosphoenolpyruvate (PEP), 1,3-bisphosphoglycerate, and creatine phosphate are -62, -49, and -43 kJ/mol, respectively. Although the breakdown of "super-high-energy" compounds, such as PEP, is not used routinely in cells to drive endergonic reactions, these compounds are still important because they can be used to drive the synthesis of ATP from ADP + Pi. In fact, this coupling, called substrate level phospohorylation, is the process by which ATP is synthesized in glycolysis.

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In cells what is the source of energy for an endergonic reaction?

In cells, the source of energy for an endergonic reaction is usually adenosine triphosphate (ATP). ATP provides the necessary energy molecule for the endergonic reactions to occur by transferring phosphate groups to molecules in order to drive the reaction forward.


What is the relationship between exergonic reactions endergonic reactions and the use and regeneration of ATP?

Exergonic reactions release energy and are spontaneous, while endergonic reactions require energy input and are non-spontaneous. ATP is used to drive endergonic reactions by providing the necessary energy for them to occur. ATP is regenerated through exergonic reactions by capturing the energy released during these reactions.


What step in glycolysis involves an endergonic reaction?

The conversion of glucose-6-phosphate to fructose-6-phosphate by phosphoglucose isomerase is an endergonic reaction in glycolysis. This step requires an input of energy in the form of ATP to drive the reaction forward.


The process of using the products of an exergonic reaction to carry out an endergonic reaction is called?

The process of using the products of an exergonic reaction to drive an endergonic reaction is known as energy coupling. This enables coupling the release of energy from one reaction to power a reaction that requires energy input. ATP is often involved in facilitating this energy transfer.


Which portion of the pathway in Figure 9.1 involves an endergonic reaction?

The portion of the pathway in Figure 9.1 that involves an endergonic reaction is the uphill segments where energy is consumed or absorbed to drive the reaction forward. Endergonic reactions require an input of energy to proceed and are typically associated with the synthesis of molecules.

Related Questions

An endergonic reaction that is driven by the splitting of ATP molecules?

In an endergonic reaction, the overall energy change is positive, requiring input of energy. By breaking down ATP molecules, which release energy, the energy released can drive the endergonic reaction forward. This coupling of the endergonic reaction with the exergonic ATP hydrolysis allows the endergonic reaction to proceed.


In cells what is the source of energy for an endergonic reaction?

In cells, the source of energy for an endergonic reaction is usually adenosine triphosphate (ATP). ATP provides the necessary energy molecule for the endergonic reactions to occur by transferring phosphate groups to molecules in order to drive the reaction forward.


What is the relationship between exergonic reactions endergonic reactions and the use and regeneration of ATP?

Exergonic reactions release energy and are spontaneous, while endergonic reactions require energy input and are non-spontaneous. ATP is used to drive endergonic reactions by providing the necessary energy for them to occur. ATP is regenerated through exergonic reactions by capturing the energy released during these reactions.


Is the Calvin cycle endergonic or exergonic?

Yes, the Calvin cycle is endergonic because it uses ATP molecules rather than creates them.


Is the pathway b-c is coupled with ADP-atp catagorize the reactions as endergonic or exergonic?

ADP-ATP is endergonic and B-C is exergonic


What is the energy shuttle between endergonic and exergonic?

ATP


What step in glycolysis involves an endergonic reaction?

The conversion of glucose-6-phosphate to fructose-6-phosphate by phosphoglucose isomerase is an endergonic reaction in glycolysis. This step requires an input of energy in the form of ATP to drive the reaction forward.


How does ATP couple exergonic and endergonic reactions?

Energy is usually released from the ATP molecule to do work in the cell by a reaction that removes one of the phosphate- oxygen groups, leaving adenosine disphosphate (ADP). When the ATP converts to ADP, the ATP is said to be spent. Then the ADP is usually immediately recycled in mitochondria where it is recharged and comes out again as ATP.


Is making ATP endergonic or exergonic?

making ATP is endergonic. This is because after ATP hydrolysis to form ADP + P, we now are at a lower energy state and for ATP to be formed again it has to be fueled by catabolic pathways, eg respiration. this energy input allows ATP to be formed and thus we see that phosphorylation of ADP requires energy input (endergonic) to form ATP. Converting ATP into ADP and P itself is EXERGONIC.


The formation of ATP from ADP is what kind of reaction?

The formation of ATP from ADP is an endergonic reaction, requiring input of energy. This energy is supplied through processes like cellular respiration.


What is the process of active transport a. Exergonic or b. endergonic?

It is b. endergonic because active transport uses ATP for energy.


Which of the following statements about the role of ATP in cell metabolism is true?

The energy from the hydrolysis of ATP may be directly coupled to endergonic processes by the transfer of the phosphate group to another molecule. A key feature in the way cells manage their energy resources to do this work is energy coupling, the use of an exergonic process to drive an endergonic one. ATP is responsible for mediating most energy coupling in cells, and in most cases it acts as the immediate source of energy that powers cellular work.