Cellular Energetics Practice Quiz 1
Settings
Quiz over AP Biology Unit 3: Cellular Energetics (Cell Respiration and Photosynthesis)
- 1.Which of the following describe(s) some aspect of metabolism?
- A.
Synthesis of macromoleculessynthesis of macromolecules
- B.
Breakdown of macromolecules
- C.
Control of enzyme activity
- D.
A and B only
- E.
A, B, and C
- 2.Which term most precisely describes the cellular process of breaking down large molecules into smaller ones?
- A.
Catalysis
- B.
Metabolism
- C.
Anabolism
- D.
Dehydration
- E.
Catabolism
- 3.Which of the following statements correctly describe(s) catabolic pathways?
- A.
They do not depend on enzymes.
- B.
They consume energy to build up polymers from monomers.
- C.
They release energy as they degrade polymers to monomers.
- D.
They lead to the synthesis of catabolic compounds.
- E.
Both A and B
- 4.Which of the following is (are) true for anabolic pathways?
- A.
They do not depend on enzymes.
- B.
They are highly regulated sequences of chemical reactions.
- C.
They consume energy to build up polymers from monomers.
- D.
They release energy as they degrade polymers to monomers.
- E.
Both B and C
- 5.What is the term for metabolic pathways that release stored energy by breaking down complex molecules?
- A.
Anabolic pathways
- B.
Catabolic pathways
- C.
Fermentation pathways
- D.
Thermodynamic pathways
- E.
Bioenergetic pathways
- 6.What is the term used for the metabolic pathway in which glucose (C6H12O6) is degraded to carbon dioxide (CO2) and water?
- A.
Cellular respiration
- B.
Glycolysis
- C.
Fermentation
- D.
Citric acid cycle
- E.
Oxidative phosphorylation
- 7.Which of the following statements concerning the metabolic degradation of glucose (C6H12O6) to carbon dioxide (CO2) and water is (are) true?
- A.
The breakdown of glucose to carbon dioxide and water is exergonic.
- B.
The breakdown of glucose to carbon dioxide and water has a free energy change of -686 kcal/mol.
- C.
LivThe breakdown of glucose to carbon dioxide and water involves oxidation-reduction or redox reactions.
- D.
Only A and B are correct.
- E.
A, B, and C are correct.
- 8.Which of the following statements is (are) correct about an oxidation-reduction (or redox) reaction?
- A.
The molecule that is reduced gains electrons.
- B.
The molecule that is oxidized loses electrons.
- C.
The molecule that is reduced loses electrons.
- D.
The molecule that is oxidized gains electrons.
- E.
Both A and B are correct.
- 9.The molecule that functions as the reducing agent (electron donor) in a redox or oxidation-reduction reaction
- A.
Gains electrons and gains energy.
- B.
Loses electrons and loses energy.
- C.
Gains electrons and loses energy.
- D.
Loses electrons and gains energy.
- E.
Neither gains nor loses electrons, but gains or loses energy.
- 10.Why does the oxidation of organic compounds by molecular oxygen to produce CO2 and water release free energy?
- A.
The covalent bonds in organic molecules are higher energy bonds than those in water and carbon dioxide.
- B.
Electrons are being moved from atoms that have a lower affinity for electrons (such as C) to atoms with a higher affinity for electrons (such as O).
- C.
The oxidation of organic compounds can be used to make ATP.
- D.
The electrons have a higher potential energy when associated with water and CO2 than they do in organic compounds.
- E.
The covalent bond in O2 is unstable and easily broken by electrons from organic molecules.
- 11.Which of the following statements describes the results of this reaction? C6H12O6 + 6 O2 --> 6 CO2 + 6 H2O + Energy
- A.
C6H12O6 is oxidized and O2 is reduced.
- B.
O2 is oxidized and H2O is reduced.
- C.
CO2 is reduced and O2 is oxidized.
- D.
C6H12O6 is reduced and CO2 is oxidized.
- E.
O2 is reduced and CO2 is oxidized.
- 12.When a glucose molecule loses a hydrogen atom (not a hydrogen ion) as the result of an oxidation-reduction reaction, the molecule becomes
- A.
Dehydrogenated.
- B.
Hydrogenated.
- C.
Oxidized.
- D.
Reduced.
- E.
An oxidizing agent.
- 13.Which of the following statements about NAD+ is false?
- A.
NAD+ is reduced to NADH during both glycolysis and the citric acid cycle.
- B.
NAD+ has more chemical energy than NADH.
- C.
NAD+ is reduced by the action of dehydrogenases.
- D.
NAD+ can receive electrons for use in oxidative phosphorylation.
- E.
In the absence of NAD+, glycolysis cannot function.
- 14.In order for NAD+ to remove electrons from glucose or other organic molecules, which of the following must be true?
- A.
The organic molecule or glucose must be negatively charged in order to reduce the positively charged NAD+.
- B.
Oxygen must be present to oxidize the NADH produced back to NAD+.
- C.
The free energy liberated when electrons are removed from the organic molecules must be greater than the energy required to give the electrons to NAD+.
- D.
A and B are both correct.
- E.
A, B, and C are all correct.
- 15.Where does glycolysis takes place?
- A.
Mitochondrial matrix
- B.
Mitochondrial outer membrane
- C.
Mitochondrial inner membrane
- D.
Mitochondrial intermembrane space
- E.
Cytosol
- 16.During glycolysis, when glucose is catabolized to pyruvate, most of the energy of glucose is
- A.
Transferred to ADP, forming ATP.
- B.
Transferred directly to ATP.
- C.
Retained in the pyruvate.
- D.
Stored in the NADH produced.
- E.
Used to phosphorylate fructose to form fructose-6-phosphate.
- 17.Why is ATP an important molecule in metabolism?
- A.
Its hydrolysis provides an input of free energy for exergonic reactions.
- B.
It provides energy coupling between exergonic and endergonic reactions.
- C.
Its terminal phosphate group contains a strong covalent bond that when hydrolyzed releases free energy.
- D.
. A and B only
- E.
A, B and C
- 18.The hydrolysis of ATP to ADP and inorganic phosphate (ATP + H2O --> ADP + Pi )
- A.
Has a G of about -7 kcal/mol under standard conditions.
- B.
Involves hydrolysis of a terminal phosphate bond of ATP.
- C.
Can occur spontaneously under appropriate conditions.
- D.
Only A and B are correct.
- E.
A, B, and C are correct.
- 19.When 10,000 molecules of ATP are hydrolyzed to ADP and Pi in a test tube, about twice as much heat is liberated as when a cell hydrolyzes the same amount of ATP. Which of the following is the best explanation for this observation?
- A.
Cells are open systems, but a test tube is a closed system.
- B.
Cells are less efficient at heat production than nonliving systems.
- C.
The hydrolysis of ATP in a cell produces different chemical products than does the reaction in a test tube.
- D.
The reaction in cells must be catalyzed by enzymes, but the reaction in a test tube does not need enzymes.
- E.
Cells convert some of the energy of ATP hydrolysis into other forms of energy besides heat.
- 20.ATP generally energizes a cellular process by
- A.
Releasing heat upon hydrolysis.
- B.
Acting as a catalyst.
- C.
Coupling free energy released by ATP hydrolysis to free energy needed by other reactions.
- D.
Breaking a high-energy bond.
- E.
Binding directly to the substrate(s) of the enzyme.
- 21.What term is used to describe the transfer of free energy from catabolic pathways to anabolic pathways?
- A.
Feedback regulationfeedback regulation
- B.
Bioenergetics
- C.
Energy coupling
- D.
Entropy
- E.
Cooperativity
- 22.Which of the following statements is true concerning catabolic pathways?
- A.
They combine molecules into more energy-rich molecules.
- B.
They are usually coupled with anabolic pathways to which they supply energy in the form of ATP.
- C.
They are endergonic.
- D.
They are spontaneous and do not need enzyme catalysis.
- E.
They build up complex molecules such as protein from simpler compounds.
- 23.Which of the following statements regarding ATP is (are) correct?
- A.
ATP serves as a main energy shuttle inside cells.
- B.
ATP drives endergonic reactions in the cell by the enzymatic transfer of the phosphate group to specific reactants.
- C.
The regeneration of ATP from ADP and phosphate is an endergonic reaction.
- D.
A and B only
- E.
A, B, and C
- 24.Which of the following statements is (are) true about enzyme-catalyzed reactions?
- A.
The reaction is faster than the same reaction in the absence of the enzyme.
- B.
The free energy change of the reaction is the same as the reaction in the absence of the enzyme.
- C.
The reaction always goes in the direction toward chemical equilibrium.
- D.
A and B only
- E.
A, B, and C
- 25.How can one increase the rate of a chemical reaction?
- A.
Increase the activation energy needed.
- B.
Cool the reactants.
- C.
Decrease the concentration of the reactants.
- D.
Add a catalyst.
- E.
Increase the entropy of the reactants.
Back to top