Chapter 7 Questions

Home > Preview

The flashcards below were created by user lduran8 on FreezingBlue Flashcards.


  1. Which of the listed statements describes the results of the following reaction?
    C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + Energy

    A) O2 is oxidized and H2O is reduced
    B) O2 is reduced and CO2 is oxidized
    C) CO2 is reduced and O2 is oxidized
    D) C6H12O6 is oxidized and O2 is reduced
    D) C6H12O6 is oxidized and O2 is reduced
    (this multiple choice question has been scrambled)
  2. Which of the following statements about NAD+ is true?

    A) NAD+ can donate electrons for use in oxidative phosphorylation
    B) NAD+ is reduced to NADH during glycolysis, pyruvate oxidation, and the citric acid cycle
    C) NAD+ has more chemical energy than NADH
    D) In the absence of NAD+, glycolysis can still function
    B) NAD+ is reduced to NADH during glycolysis, pyruvate oxidation, and the citric acid cycle
    (this multiple choice question has been scrambled)
  3. When a molecule of NAD+ (nicotinamide adenine dinucleotide) gains a hydrogen atom (not a proton), the molecule becomes ___.

    A) dehydrogentated
    B) reduced
    C) redoxed
    D) oxidized
    B) reduced
    (this multiple choice question has been scrambled)
  4. Glycolysis is __.

    A) The electron transport chain
    B) The process of oxidation of acetyl CoA
    C) The process of oxidation of glucose into two molecules of pyruvate
    D) The process of building and storing glucose molecules
    C) The process of oxidation of glucose into two molecules of pyruvate
    (this multiple choice question has been scrambled)
  5. In glycolysis, for each molecule of glucose oxidized to pyruvate ___.

    A) two molecules of ATP are used and four molecules of ATP are produced
    B) two molecules of ATP are used and six molecules of ATP are produced
    C) two molecules of ATP are used and two molecules of ATP are produced
    D) four molecules of ATP are used and two molecules of ATP are produced
    A) two molecules of ATP are used and four molecules of ATP are produced
    (this multiple choice question has been scrambled)
  6. The free energy for the oxidation of glucose to CO2 and water is -686 kcal/mol and the free energy for the reduction of NAD+ to NADH is +53kcal/mol. Why are only two molecules of NADH formed during glycolysis when it appears that as many as a dozen could be formed?

    A) Most of the free energy available from the oxidation of glucose is used in the production of ATP in glycolysis
    B) Most of the free energy available from the oxidation of glucose remains in pyruvate, one of the products of glycolysis
    C) There is no CO2 or water produced as products of glycolysis
    D) Glycolysis is a very inefficient reaction, with much of the energy of glucose released as heat
    B) Most of the free energy available from the oxidation of glucose remains in pyruvate, one of the products of glycolysis
    (this multiple choice question has been scrambled)
  7. The type of enzyme that adds a phosphate to its substrate is referred to as a ___.

    A) kinase
    B) isomerase
    C) peptidase
    D) dehydrogentated
    A) kinase
    (this multiple choice question has been scrambled)
  8. The first step of glycolysis expends energy through the addition of phosphate to glucose, resulting in glucose-6-phosphate. Which of these enzymes is most likely responsible for catalyzing this reaction?

    A) Phosphoglyceromutase
    B) Glyceraldehyde-3-phosphate dehydrogenase
    C) Phosphoglucose isomerase
    D) Hexokinase
    D) Hexokinase
    (this multiple choice question has been scrambled)
  9. What is the difference between the citric acid cycle, the TCA cycle, and the Krebs cycle?

    A) The Krebs cycle is responsible for ATP production whereas the TCA and citric acid cycles are responsible for the reduction of NADH
    B) The Krebs cycle and TCA cycle only occur in animal cells, but the citric acid cycle only occurs in prokaryotes
    C) These names all refer to the same process
    D) The TCA and the citric acid cycles break down glucose, whereas the Krabs cycle breaks down fatty acids.
    C) These names all refer to the same process
    (this multiple choice question has been scrambled)
  10. In the presence of oxygen, the three-carbon compound pyruvate can be catabolized in the citric acid cycle. First, however, the pyruvate (1) loses a carbon, which is given off as a molecule of CO2, (2) is oxidized to form a two-carbon compound called acetate, and (3) is bonded to co-enzyme A

    The three listed steps result in the formation of __.

    A) acetyl CoA, FADH, and CO2
    B) acetyl CoA, NADH, and CO2
    C) acetyl CoA, NAD+, ATP, and CO2
    D) acetyl CoA, O2, and ATP
    B) acetyl CoA, NADH, and CO2
    (this multiple choice question has been scrambled)
  11. ___ is the initial substrate of the TCA cycle, and ___ is the final product of the TCA cycle.

    A) Oxaloacetate; Citrate
    B) Citrate; Oxaloacetate
    C) Acetly CoA; Oxaloacetate
    D) Oxaloacetate; Acetyl CoA
    C) Acetly CoA; Oxaloacetate
    (this multiple choice question has been scrambled)
  12. Which of these is not a substrate of the citric acid cycle (TCA cycle)?

    A) Citrate
    B) Glucose
    C) Acetyl CoA
    D) Succinate
    B) Glucose
    (this multiple choice question has been scrambled)
  13. If glucose is the sole energy source, what fraction of the carbon dioxide exhaled by animals is generated by the reactions of the citric acid cycle?

    A) 1/3
    B) 1/6
    C) 2/3
    D) All of it
    C) 2/3
    (this multiple choice question has been scrambled)
  14. In chemiosmosis, what is the most direct source of energy that is used to convert ADP + i to ATP?

    A) No external source of energy is required because the reaction is exergonic
    B) Energy released from substrate-level phophorylation
    C) Energy released from movement of protons through ATP synthase, down their electrochemical gradient
    D) Energy released as electrons flow through the electron transport system
    C) Energy released from movement of protons through ATP synthase, down their electrochemical gradient
    (this multiple choice question has been scrambled)
  15. The synthesis of ATP by oxidative phosphorylation, using the energy released by movement of protons across the membrane down their electrochemical gradient, is an example of ___.

    A) a reaction with a positive ΔG
    B) an endergonic reaction coupled to an exergonic reaction
    C) active transport
    D) allosteric regulation
    B) an endergonic reaction coupled to an exergonic reaction
    (this multiple choice question has been scrambled)
  16. Following glycolysis and the citric acid cycle, but before the electron transport chain and oxidative phosphorylation, the carbon skeleton of glucose has been broken down to CO2 with some net gain of ATP. Most of the energy from the original glucose molecule at that point in the process, however, is in the form of ___.

    A) glucose
    B) pyruvate
    C) NADH
    D) Acetyl CoA
    C) NADH
    (this multiple choice question has been scrambled)
  17. Chemiosmotic ATP synthesis (oxidative phosphorylation) occurs in ___.

    A) all cells, but only in the presence of oxygen
    B) only in mitochondria, using either oxygen or other electron acceptors
    C) only eukaryotic cells, in the presence of oxygen
    D) all respiring cells, both prokaryotic and eukaryotic, using either oxygen or other electron acceptors
    D) all respiring cells, both prokaryotic and eukaryotic, using either oxygen or other electron acceptors
    (this multiple choice question has been scrambled)
  18. Exposing the inner motochondrial membranes to ultrasonic vibrations will disrupt the membranes. However, the fragments will reseal "inside out." The little vesicles that result can still transfer electrons from NADH to oxygen and synthesize ATP.

    After the disruption, when electron transfer and ATP synthesis still occur, what must be present?

    A) The electron transport system
    B) The ATP synthase system
    C) All of the electron transport proteins and ATP synthase
    D) All of the electron transport system and the ability to add CoA to acetyl groups
    C) All of the electron transport proteins and ATP synthase
    (this multiple choice question has been scrambled)
  19. A young dog has never had much energy. He is brought to a veterinarian for help and she decides to conduct several diagnostic tests. She discovers that the dog's mitochondria can use only fatty acids and amino acids for respiration, and his cells produce more lactate than normal. Of the following, which is the best explanation of the dog's condition?

    A) His cells cannot move NADH from glycolysis into the mitochondria
    B) His cells lack the enzyme in glycolysis that forms pyruvate
    C) His mitochondria lack the transport protein that moves pyruvate across the outer mitochondrial membrane
    D) His cells have a defective electron transport chain, so glucose goes to lactate instead of to acetyl CoA
    C) His mitochondria lack the transport protein that moves pyruvate across the outer mitochondrial membrane
    (this multiple choice question has been scrambled)
  20. The oxidation of a molecule of glucose (a 6-carbon sugar) results in two molecules of pyruvate, or 2 molecules of acetyl CoA. During the oxidation of glucose, 2 carbons are lost and only 4 are able to enter the TCA cycle as acetyl CoA. By comparison, the beta oxidation of fatty acids breaks fatty acids into 2-carbon units, which are each used to generate acetyl CoA

    A) 2 molecules of glucose
    B) Neither can be oxidized by eukaryotic cels
    C) Both have 12 carbons and would therefore be the same
    D) A 12-carbon fatty acid
    D) A 12-carbon fatty acid
    (this multiple choice question has been scrambled)
  21. Even though plants cells photosynthesize, they still use their mitochondria for oxidation of pyruvate. This will occur in __.

    A) all cells all the time
    B) photosynthesizing cells in the light and in other tissues in the dark
    C) photosynthetic cells in the light, while photosynthesis occurs concurrently
    D) cells that are storing glucose only
    A) all cells all the time
    (this multiple choice question has been scrambled)
  22. Which of the following normally occurs regardless of whether or not oxygen (O2) is present?

    A) Citric acid cycle
    B) Glycolysis
    C) Fermentation
    D) Oxidative phosphorylation (chemiosmosis)
    B) Glycolysis
    (this multiple choice question has been scrambled)
  23. One function of both alcohol fermentation and lactic acid fermentation is to __.

    A) reduce NAD+ to NADH
    B) reduce FADH2 to FAD+
    C) reduce FAD+ to FADH2
    D) oxidize NADH to NAD+
    D) oxidize NADH to NAD+
    (this multiple choice question has been scrambled)
  24. A cell has enough available ATP to meet its needs for about 30 seconds. What is likely to happen when an athlete exhausts his or her ATP supply?

    A) He or she has to sit down and rest.
    B) ATP is transported into the cell from the circulatory system
    C) Catabolic processes are activated that generate more ATP
    D) Other cells take over, and the muscle cells that have used up their ATP cease to function
    C) Catabolic processes are activated that generate more ATP
    (this multiple choice question has been scrambled)
  25. Approximately how many molecules of ATP are produced from the complete oxidation of one molecule of glucose (C6H12O6) in aerobic cellular respiration?

    A) 2
    B) 4
    C) Around 36
    D) 18
    C) Around 36
    (this multiple choice question has been scrambled)
  26. Carbohydrates and fats are considered high-energy foods because they ___.

    A) have no nitrogen in their makeup
    B) have a lot of electrons associated with hydrogen
    C) have a lot of oxygen atoms
    D) are easily reduced
    B) have a lot of electrons associated with hydrogen
    (this multiple choice question has been scrambled)
  27. The oxygen consumed during cellular respiration is involved directly in which process or event?

    A) The process of building and storing glucose molecules
    B) Glycolysis
    C) The citric acid cycle
    D) Accepting electrons at the end of the electron transport chain
    D) Accepting electrons at the end of the electron transport chain
    (this multiple choice question has been scrambled)
  28. When electrons move closer to a more electronegative atom, what happens? The more electronegative atom is ___.

    A) oxidized, and energy is released
    B) reduced, and energy is released
    C) oxidized, and energy is consumed
    D) reduced, and energy is consumed
    B) reduced, and energy is released
    (this multiple choice question has been scrambled)
  29. In the initial "energy investment" stage of glycolysis, which enzymes are responsible for using ATP to transfer a phosphate to glucose (or its derivatives)?

    A) The process of building and storing glucose molecules
    B) Kinases
    C) Glycolysis
    D) oxidized, and energy is consumed
    B) Kinases
    (this multiple choice question has been scrambled)
  30. ___ is/ are the starting substrate and ___ is/are the end product of the glycolysis pathway

    A) 1 molecule of glucose; 2 molecules of pyruvate
    B) 1 molecule of fatty acid; 8 molecules of pyruvate
    C) 1 molecule of glucose; 2 molecules of acetyl CoA
    D) 1 molecule of pyruvate; 2 molecules of glucose
    A) 1 molecule of glucose; 2 molecules of pyruvate
    (this multiple choice question has been scrambled)
  31. Which electron carrier(s) function in the citric acid cycle?

    A) NADH and FADH2
    B) The electron transport chain
    C) ADP and ATP
    D) NAD+ only
    A) NADH and FADH2
    (this multiple choice question has been scrambled)
  32. In the presence of oxygen, the three-carbon compound pyruvate (1) loses a carbon, which is given off as a molecule of CO2, (2) is oxidized to form a two-carbon compound called acetate, and (3) is bonded to coenzyme A.

    Which one of the following is formed by the removal of a carbon (as CO2) from a molecule of pyruvate?

    A) Citrate
    B) acetyl CoA
    C) Glyceraldehyde 3-phosphate
    D) Oxaloacetate
    B) acetyl CoA
    (this multiple choice question has been scrambled)
  33. Energy released by the electron transport chain is used to pump H+ into which location in eukaryotic cells?

    A) Mitochondrial matrix
    B) Mitochondrial intermembrane space
    C) Mitochondrial inner membrane
    D) Mitochondrial outer membrane
    B) Mitochondrial intermembrane space
    (this multiple choice question has been scrambled)
  34. When hydrogen ions are pumped from the mitochondrial matrix across the inner membrane and into the intermembrane space, the result is the

    A) formation of ATP
    B) creation of a proton-motive force
    C) lowering the pH in the mitochondrial matrix
    D) reduction of NAD+
    B) creation of a proton-motive force
    (this multiple choice question has been scrambled)
  35. The electron transport chain ___.

    A) is a series of redox reactions
    B) takes place in the cytoplasm of prokaryotic cells
    C) is a series of substitution reactions
    D) is driven by ATP consumption
    A) is a series of redox reactions
    (this multiple choice question has been scrambled)
  36. You have a friend who lost 7 kg (about 15 pounds) of fat on a regimen of strict diet and exercise. How did the fat leave his body?

    A) It was converted to ATP, which weighs much less than fat
    B) It was converted to heat and then released
    C) It was released as CO2 and H2O
    D) It was converted to urine and eliminated from the body
    C) It was released as CO2 and H2O
    (this multiple choice question has been scrambled)
  37. In the absence of oxygen, yeast cells can obtain energy by fermentation, resulting in the production of __.

    A) ATP, pyruvate, and acetyl CoA
    B) ATP, NADH, and pyruvate
    C) ATP, CO2, and ethanol (ethyl alcohol)
    D) ATP, CO2, and lactate
    C) ATP, CO2, and ethanol (ethyl alcohol)
    (this multiple choice question has been scrambled)
  38. Why is glycolysis considered to be one of the first metabolic pathways to have evolved?

    A) It is found in prokaryotic cells
    B) It produces much less ATP than does oxidative phosphorylation
    C) It requires the presence of membrane-enclosed cell organelles found only in eukaryotic cells.
    D) It does not involve organelles or specialized structures, does not require oxygen, and is present in most organisms.
    D) It does not involve organelles or specialized structures, does not require oxygen, and is present in most organisms.
    (this multiple choice question has been scrambled)
  39. The electron transport chain can use a single molecule of NADH to generate 3 ATPs and a single molecule of FADH2 to generate 2 ATPs. Imagine that you have a single glucose molecule. How many ATPs would be generated per molecule of acetyl CoA that enters the TCA cycle (following oxidation of one glucose molecule), if you only count ATP generated from NADH or FADH2 in the electron transport chain? For this question, use only NADH and FADH2 that is generated through the TCA cycle.

    A) 11
    B) 36
    C) 22
    D) 28
    C) 22
    (this multiple choice question has been scrambled)
  40. The molecule that functions as the reducing agent (electron donor) in a redox or oxidation-reduction reaction ___.

    A) gains electrons and gains potential energy
    B) loses electrons and gains potential energy
    C) gains electrons and loses potential energy
    D) loses electrons and loses potential energy
    D) loses electrons and loses potential energy
    (this multiple choice question has been scrambled)
  41. What is the oxidizing agent in the following reaction? 

    Pyruvate + NADH + H+ → Lactate + NAD+

    A) NADH
    B) Lactate
    C) NAD+
    D) Pyruvate
    D) Pyruvate
    (this multiple choice question has been scrambled)
  42. Glycolysis is active when cellular energy levels are ___; the regulatory enzyme, phosphofructokinase, is __ by ATP

    A) low; activated
    B) high; activated
    C) high; inhibited
    D) low; inhibited
    D) low; inhibited
    (this multiple choice question has been scrambled)
  43. Which of the following is not true of glycolysis?

    A) Glycolysis does not refer to the breakdown of fatty acids
    B) Glycolysis requires O2
    C) Glycolysis is the breakdown of glucose into pyruvate
    D) Glycolysis results in the storage of more energy than it expends, though some energy is expended
    B) Glycolysis requires O2
    (this multiple choice question has been scrambled)
  44. During the second phase of glycolysis, where energy is "generated", which type of enzyme uses the reduction of NAD+ to NADH in order to "store" energy?

    A) Dehydrogenases
    B) Polymerases
    C) Isomerases
    D) Kinases
    A) Dehydrogenases
    (this multiple choice question has been scrambled)
  45. If pyruvate oxidation is blocked, what will happen to the levels of oxaloacetate and citric acid in the citric acid cycle?

    A) Oxaloacetate will decrease and citric acid will accumulate
    B) Both oxaloacetate and citric acid will accumulate
    C) Oxaloacetate will accumulate and citric acid will decrease
    D) Both oxaloacetate and citric acid will decrease
    C) Oxaloacetate will accumulate and citric acid will decrease
    (this multiple choice question has been scrambled)
  46. Carbon dioxide (CO2) is released during which of the following stages of cellular respiration?

    A) Fermentation and glycolysis
    B) Oxidative phosphorylation and fermentation
    C) Oxidation of pyruvate to acetyl CoA and the citric acid cycle
    D) Glycolysis and the oxidation of pyruvate to acetyl CoA
    C) Oxidation of pyruvate to acetyl CoA and the citric acid cycle
    (this multiple choice question has been scrambled)
  47. Starting with citrate, which of the following combinations of products would result form three acetyl CoA molecules entering the citric acid cycle?

    A) 3 ATP, 6 CO2, 9 NADH, and 3 FADH2
    B) 38 ATP, 6 CO2, 3 NADH, and 12 FADH2
    C) 1 ATP, 2 CO2, 3 NADH, and 1 FADH2
    D) 3 ATP, 3 CO2, 3 NADH, and 3 FADH2
    A) 3 ATP, 6 CO2, 9 NADH, and 3 FADH2
    (this multiple choice question has been scrambled)
  48. Which of the following events takes place in the electron transport chain?

    A) The extraction of energy from high-energy elecytrons remaining from glycolysis and the citric acid cycle
    B) Substrate-level phosphorylation
    C) The breakdown of glucose into two pyruvate molecules
    D) The breakdown of an acetyl group to carbon dioxide
    A) The extraction of energy from high-energy elecytrons remaining from glycolysis and the citric acid cycle
    (this multiple choice question has been scrambled)
  49. The oxidation of a molecule of glucose (a 6-carbon sugar) results in two molecules of pyruvate, or 2 molecules of acetyl CoA. During the oxidation of glucose, 2 carbons are lost and only 4 are able to enter the TCA cycle as acetyl CoA. By comparison, the beta oxidation of fatty acids breaks fatty acids into 2-carbon units, which are each used to generate acetyl CoA. 

    Based on this information, which of these starting molecules would produce the most ATP if completely oxidized by a eukaryotic cell and used to drive oxidative phosphorylation of ATP?

    A) 3 molecules of glucose
    B) Neither can be used by eukaryotic cells
    C) 3 molecules of glucose and one molecule of a 12-carbon fatty acid have the same useable amount of carbons to make acetyl CoA, so they would be basically the same
    D) One molecule of a 12-carbon fatty acid
    C) 3 molecules of glucose and one molecule of a 12-carbon fatty acid have the same useable amount of carbons to make acetyl CoA, so they would be basically the same
    (this multiple choice question has been scrambled)
  50. In respiration, beta oxidation involves the ___.

    A) breakdown of fatty acids
    B) oxidation of pyruvate
    C) oxidation of glucose
    D) regulation of glycolysis
    A) breakdown of fatty acids
    (this multiple choice question has been scrambled)
  51. Yeast cells that have defective mitochondria incapable of respiration will be able to grow by catabolizing which of the following carbon sources for energy?

    A) Fatty acids
    B) Such yeast cells will not be capable of catabolizing any food molecules, and therefore, will die.
    C) Glucose
    D) Proteins
    C) Glucose
    (this multiple choice question has been scrambled)
  52. High levels of citric acid inhibit the enzyme phosphofructokinase, a key in enzyme glycolysis. Citric acid binds to the enzyme at a different location from the active site. This is an example of ___.

    A) allosteric regulation
    B) competitive inhibition
    C) the specificity of enzymes for their substrates
    D) positive feedback regulation
    A) allosteric regulation
    (this multiple choice question has been scrambled)
  53. If a cell is able to synthesize 30 ATP molecules for each molecule of glucose completely oxidized to carbon dioxide and water, approximately how many ATP molecules can the cell synthesize for each molecule or pyruvate oxidized to carbon dioxide and water?

    A) 15
    B) 60
    C) 30
    D) 0
    A) 15
    (this multiple choice question has been scrambled)

Card Set Information

Author:
lduran8
ID:
329292
Filename:
Chapter 7 Questions
Updated:
2017-03-09 08:18:38
Tags:
chapter7 questions biology
Folders:
biology2
Description:
questions from chapter 7
Show Answers:

Home > Flashcards > Print Preview