Bio 101 Exam (Chapter 4)

7. When energy is converted from one form to another:

a) some energy is converted to heat.

37. Which of the following sequences accurately represents the flow of electrons during photosynthesis?

a) H2O → NADPH → Calvin cycle

30. Photosystems are:

a) arrangements of light-catching pigments within chloroplasts.

48. Cellular respiration is the process by which:

a) energy from the chemical bonds of food molecules is captured by an organism.

39. During the Calvin cycle, rubisco's function is to:

a) fix carbon to RuBP (ribulose bisphosphate).

55. Which of the following energy-generating processes is the only one that occurs in all living organisms?

a) glycolysis.

50. Aerobic bacteria:

a) lack mitochondria.

66. Fermentation reactions generally occur under conditions of:

a) low oxygen concentrations.

18. Biologically speaking, a pigment is a:

a) molecule that absorbs a photon.

15. Which by-product of photosynthesis was important in altering the atmosphere of the earth so that aerobic organisms could evolve?

a) oxygen

47. During C4 photosynthesis:

a) plants are able to continue producing sugars even when they must close their stomata to reduce water loss during hot days.

24. Which of the following does NOT occur as a direct result of a photon hitting a chlorophyll molecule?

a) production of NADPH and H+

23. A plant with leaves that are reddish yellow is NOT absorbing light from which wavelengths of the visible light spectrum?

a) red and yellow

32. Photosynthesizing plants rely on water to:

a) replace electrons that are excited by light energy and passed from molecule to molecule down an electron transport chain.

40. The most abundant protein in the world is the enzyme that initiates the fixation of carbon in the Calvin cycle. This enzyme is called:

a) rubisco.

59. During the Krebs cycle:

a) the products of glycolysis are further broken down, generating additional ATP and the high-energy electron carrier NADH.

8. Within the study of thermodynamics, a closed system is defined as system in which energy does not come in and energy does go out. Which of the following is considered a closed system?

a) the universe

14. A green plant can perform photosynthesis if given nothing more than:

a) water, light, and air.

38. Which of the following would be a typical product of the dark reactions of photosynthesis?

b) 3-phosphoglycerate acid (3-PGA)

12. Energy is released as ATP becomes ADP when:

b) ATP ejects one of its phosphate groups.

16. If a thylakoid were punctured so that its interior was no longer separated from the stroma, which of the following processes would be affected most directly?

b) ATP synthesis

46. The three different known biochemical pathways organisms will use to photosynthesize include which of the following?

b) C3, C4, CAM

53. Which of the following statements about glycolysis is INCORRECT?

b) It requires oxygen.

28. Which of the following statements about the DIFFERENCES between the chlorophyll a molecule at the center of a photosystem and chlorophyll elsewhere in the photosystem is NOT true?

b) The excited electrons in chlorophyll a at the reaction center return to their resting state, while the excited electrons in chlorophyll a away from the photosystem center are transferred to the primary electron acceptor.

17. Carotenoids:

b) are more abundant in leaves in the fall than either chlorophyll a or b.

49. Photosynthesis is the process by which plants, some bacteria, and some protistans use the energy from sunlight to produce sugar, which _______________ converts to ATP, the "fuel" used by all living things.

b) cellular respiration

26. Chlorophyll's most important role during photosynthesis is:

b) converting light energy from the sun into chemical energy.

56. What are the three different metabolic pathways that are responsible for the production of ATP?

b) glycolysis, the reactions on the electron transport chain, and the Krebs (citric acid) cycle

44. Where does the Calvin cycle take place?

b) in the stroma of the chloroplast

20. Chlorophyll b and the carotenoids are important as receptors of light energy because they:

c) respond to wavelengths different from the wavelengths to which chlorophyll a responds

41. How many rotations of the Calvin cycle are required for the production of one glucose molecule?

c) 6

42. To synthesize one glyceraldehyde 3-phosphate (G3P) molecule, the Calvin cycle has to fix three atoms of carbon from carbon dioxide to an organic molecule within the chloroplast. This process consumes how many molecules of ATP and NADPH, respectively, which were generated in the "photo" reactions?

c) 9, 6

33. The light reactions of photosynthesis supply the Calvin cycle with:

c) ATP and NADPH & H+.

27. Energized electrons from the water-splitting photosystem pass down an electron transport chain to the ___________-producing photosystem.

c) NADPH

58. In glycolysis, one molecule of glucose containing six carbons is converted to two molecules of ________ containing six carbons each. This reaction also yields two molecules of _______ and two molecules of _______.

c) pyruvate; ATP; NADH

6. Which of the following is NOT a form of kinetic energy?

c) a covalent bond linking phosphate molecules

67. All alcoholic beverages are produced as the result of cellular respiration:

c) by yeast occurring in the absence of oxygen.

60. An inherited disease results from abnormal mitochondria passed from mother to child. Using your knowledge of mitochondria's function within human cells, which of the following is the most likely description of the symptoms of this disease?

c) extreme muscle weakness

45. The C4 mechanism of carbon fixation is an advantage for plants that live in:

c) hot, dry climates.

5. Potential energy:

c) is contained in matter placed in certain positions or arrangements.

65. In animals, exertion without sufficient oxygen leads to the production of:

c) lactic acid.

31. Bubbles come from the leaves of an elodea plant when it is put under water because:

c) oxygen is a by-product of photosynthesis.

19. The graphs above show data relating to seasonal differences in the amount of pigment molecules present in leaves and how this is related to leaves changing colors. What is the dependent variable presented in these graphs?

c) the measure of the amount of each pigment molecule present in leaves

34. Which of the following statements about the light reactions of photosynthesis are correct?

d) All of the above are correct. a) The energy of the sun is captured as potential energy. b) Pigments absorb light energy, which excites electrons. c) Water molecules split, providing a source of electrons.

2. Which of the following statements is FALSE?

d) Burning fossil fuels releases energy, oxygen, and water.

68. Which of the following statements about fermentation is TRUE?

d) Fermentation uses electrons generated from glycolysis and the Krebs cycle.

70. Which of the following is TRUE regarding the metabolic machinery of humans and animals?

d) Humans and animals can extract energy from sugars, lipids, and proteins.

1. Which one of the following statements best represents the relationship between respiration and photosynthesis?

d) Photosynthesis stores energy in complex organic molecules, while respiration releases it.

21. When a photon strikes a molecule, the photon may do any of the following EXCEPT:

d) be oxidized by an electron from the valence shell of the molecule.

13. Which of the following is NOT a product of photosynthesis?

d) carbon dioxide

51. The outputs of cellular respiration are:

d) carbon dioxide, water, and ATP.

29. What are the resulting products of the splitting of water in photosynthesis?

d) electrons, oxygen, and hydrogen ions

36. Oxygen gas produced during photosynthesis originates as:

d) oxygen atoms contained in water molecules.

52. The ultimate result of glycolysis is two molecules of:

d) pyruvate.

61. In your body, when energy is released from the breakdown of a molecule such as glucose:

d) some of the energy may be harnessed by building the unstable high-energy bonds that attach phosphate groups to ADP.

43. Which of the following does NOT occur during the Calvin cycle?

d) splitting of water

9. Different steps in cellular respiration occur in different locations in the mitochondria. Which of the following does not properly match a step of respiration to its proper location?

e) All of the above are correct matches between function and location. a) molecule of CO2 released: matrix b) two carbons manipulated through Krebs cycle: matrix c) energy transferred from NADH and FADH2 to ATP: inner mitochondrial membrane d) a gradient of hydrogen ions phosphorylates ATP: inner mitochondrial membrane

11. The phosphate groups in ATP:

e) All of the above are correct. a) represent a significant source of stored energy. b) release energy when separated from the rest of the molecule. c) are covalently bonded to each other. d) are negatively charged.

64. Cyanide is such a deadly poison because it:

e) Both a and b are correct. a) blocks the passage of electrons to oxygen in the electron transport chain. b) effectively halts the production of ATP within mitochondria.

62. Which of the following is a feature of mitochondria that aids in their unique ability to harness energy from food?

e) Both a and c are correct a) "bag-within-a-bag" structure c) inner "bag" structure studded with electron carrier molecules

22. The most effective portion(s) of the visible spectrum in driving photosynthesis is(are):

e) Both a and c are correct. a) the violet-blue c) the red-orange portion.

4. A cyclist rides her bike up a very steep hill. Which of the following choices properly describes this example in energetic terms?

e) Both a and d are correct. a) Potential energy in food is converted to kinetic energy as muscles push the cyclist up the hill d) Gravity provides a source of potential energy.

63. The generation of ATP by the movement of protons down their concentration gradient occurs in:

e) Only a and b are correct a) mitochondria. b) chloroplasts.

69. In cellular respiration, energy-rich:

e) Only the first three choices are correct a) carbohydrate molecules are oxidized to carbon dioxide and water. b) fat molecules are oxidized to carbon dioxide and water. c) sugar molecules are oxidized to carbon dioxide and water.

10. Each ATP molecule is composed of three separate subunits. Which of the following is NOT a proper description of one of these subunits?

e) a triphosphate group

57. Energy derived from cellular respiration can originate from:

e) carbohydrates, proteins, and fats.

25. During photosynthesis, visible light has enough energy to:

e) excite electrons.

54. Glycolysis:

e) occurs in all cells.

3. Life gains most of its energy from:

e) sunlight

35. The electron transport chain in eukaryotic mitochondria results in all of the following EXCEPT:

e) the breakdown of glycogen to glucose.