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Example Questions
Example Question #3 : Understand Atp Coupling
If the reaction for ATP hydrolysis 
Through ATP coupling, the hydrolysis of ATP can allow the second, thermodynamically unfavorable reaction to proceed. 
Example Question #1 : Understand Structure And Importance Of Atp
Which is NOT a reason that the phosphoanhydride bonds of ATP are high energy?
Resonance stabilization of products of ATP hydrolysis
Large mass of phosphate provides significant energy when combusted
Entropy is increased when bonds are broken
Repulsion of positively charged phosphate and negatively charged oxygen
Large mass of phosphate provides significant energy when combusted
The phosphoanhydride bonds of ATP, or the bonds between phosphate molecules, are high energy. This is due to the close proximity of positively charged phosphate and negatively charged oxygen; these charges repel. Also, there is resonance stabilization of the products of ATP hydrolysis (ADP and Pi); thus ADP is more stable than ATP. Additionally, entropy is increased when ATP is hydrolyzed; the second law of thermodynamics states that the entropy of a system always increases.
Example Question #2 : Cellular Energetics
Which is not part of an ATP molecule?
ribose sugar
adenine
alpha phosphate, beta phosphate, and gamma phosphate groups
threonine
threonine
ATP consists of 3 phosphate groups, a ribose sugar, and adenine.
Example Question #2 : Understand Structure And Importance Of Atp
Which is true of an ATP molecule?
When hydrolyzed, delta G> 0
When hydrolyzed, a phosphoanhydride bond is formed
It is used for long-term energy storage
It is unstable
It is unstable
ATP is unstable; there is close proximity of positively charged phosphate and negatively charged oxygen; these charges repel. When hydrolyzed, delta G is <0 (exergonic). ATP is not used for long term-energy storage, as it is unstable. When hydrolyzed, a phosphoanhydride bond is broken.
Example Question #1 : Understand Structure And Importance Of Atp
Which is true of ADP
It contains 2 phosphate groups
ATP is produced when ADP is broken down
It contains more energy than ATP
It contains 3 phosphate groups
It contains 2 phosphate groups
When ATP is hydrolyzed and a phosphoanhydride bond is broken, ADP and a phosphate are the products. ADP then has 2 phosphate groups.
Example Question #11 : Cellular Energetics
Which cellular process produces ATP?
mitosis
DNA synthesis
Na+/K+ pump
Cellular respiration
Cellular respiration
Cellular respiration is the process through which ATP is produced through the oxidation of glucose.
Example Question #12 : Cellular Energetics
What is the primary energy currency for cells?
ATP
GTP
oxygen
carbohydrate
ATP
ATP is the primary energy currency for cells. The phosphoanhydride bonds of ATP, or the bonds between phosphate molecules, are high energy. This is due to the close proximity of positively charged phosphate and negatively charged oxygen; these charges repel. Also, there is resonance stabilization of the products of ATP hydrolysis (ADP and Pi); thus ADP is more stable than ATP. Carbohydrates are broken down during glycolysis to produce ATP.
Example Question #1 : Understand Pyruvate Decarboxylation
During pyruvate decarboxylation reaction, pyruvate is converted to _______________ compound, through a reaction called ______________ .
NADH; oxidative decarboxylation
acetyl CoA; oxidative decarboxylation
ATP; decomposition
acetyl CoA; reductive decarboxylation
acetyl CoA; oxidative decarboxylation
Pyruvate decarboxylation is an oxidative decarboxylation reaction, or an oxidation reaction where a carboxylate group is removed. This reaction converts pyruvate which was produced through glycolysis to acetyl CoA to be used in the Citric Acid Cycle.
Example Question #1 : Understand Pyruvate Decarboxylation
Which enzyme complex catalyzes the pyruvate decarboxylation reaction?
pyruvate dehydrogenase complex
acetyl dehydrogenase
pyruvate reductase
pyruvate oxidase
pyruvate dehydrogenase complex
The pyruvate dehydrogenase complex is an enzyme complex that consists of 3 enzymes, which work together to catalyze the pyruvate decarboxylation reaction, where pyruvate is converted to acetyl CoA.
Example Question #3 : Understand Pyruvate Decarboxylation
Where does the pyruvate decarboxylation reaction occur?
Cristae
Outer mitochondrial membrane
Mitochondrial matrix
Cytosol
Mitochondrial matrix
Pyruvate decarboxylation occurs in the mitochondrial matrix. The acetyl CoA produced from the pyruvate decarboxylation reaction will undergo the Citric Acid cycle also in the mitochondrial matrix.
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