Biology Exam 3

Question 1

1. Why do we have storage macromolecules, such as fats, in our bodies?

Answer 1

a.We can break down these macromolecules to provide energy for the endergonic reactions in our bodies.

Question 2

2. Energy is defined as

Answer 2

b. The capacity to do work

Question 3

3. A calorie is a commonly used unit of chemical energy. It is also the unit of

Answer 3

d. Heat

Question 4

5. Oxidation and reduction reactions are chemical processes that result in a gain or loss of

Answer 4

c. Electrons

Question 5

6. When an atom or molecule gains one or more electrons, it is said to be

Answer 5

d. Reduced

Question 6

7. The term oxidation is derived from the name of the element oxygen. This is reasonable, because oxygen.

Answer 6

a. Attracts electrons very strongly

Question 7

8. The energy used by humans ultimately originates from what source?

Answer 7

a. The sun

Question 8

9. The Law of Thermodynamics that states that energy cannot be created or destroyed is the

Answer 8

a. First Law of Thermodynamics

Question 9

10. You eat a bowl of beans as part of your dinner. As you digest the beans, the proteins that are present get broken down to their component amino acids. As your body destroys the macromolecules that were present in the beans, is the energy present in those molecules destroyed?

Answer 9

c. No. the energy contained within these macromolecules is converted into other forms of chemical energy and kinetic energy, through some is lost as heat.

Question 10

11. If were you able to increase the kinetic energy of the molecules inside your body, how would this affect your body temperature?

Answer 10

a. It would increase.

Question 11

12. The Law of Thermodynamics that states that increases in entropy are favored is the

Answer 11

b. Second Law of Thermodynamics

Question 12

13. The amount of energy available to do work is called

Answer 12

b. Free energy

Question 13

14. In an enzyme-catalyzed reaction, the reactant is called the

Answer 13

C. Substrate

Question 14

15. When the substrate is bound to the enzyme, the shape of the enzyme may change slightly leading to

Answer 14

a. An induced fit

Question 15

16. A drug binds to the active site of an enzyme. If it is bound to the active site of the enzyme, it prevents substrate binding. This drug would be considered a

Answer 15

d. Competitive inhibitor

Question 16

17. A molecule that closely resembles the shape of a substrate for an enzyme would most likely serve as a

Answer 16

c. Competitive inhibitor

Question 17

18. The chemistry of living systems representing all chemical reactions is called

Answer 17

c. Metabolism

Question 18

19. Organisms that can manufacture their own chemical energy are called

Answer 18

a.Autotrophs

Question 19

20. Organisms that depend on the energy stored in chemical bonds by other organisms for their food energy are called

Answer 19

b.Heterotrophs

Question 20

21. In animals that take in oxygen from their environment, glucose is broken down into carbon dioxide and water in a process called

Answer 20

d.Aerobic respiration

Question 21

22. To form NADH from NAD* two electrons and a proton are removed from an organic molecule. What term best describes the reaction in which electrons are removed from an organic molecule?

Answer 21

d. decarboxylation

Question 22

23. What is the oxidized form of the most common electron carrier that is needed for both glycolysis and the citric acid cycle?

Answer 22

d. NAD+

Question 23

24. What aspect of cellular respiration occurs in the cytoplasm in eukaryotic cells?

Answer 23

a. Glycolysis

Question 24

25. In glycolysis, a major portion of the energy remains in the final product, which is called

Answer 24

d. Pyruvate

Question 25

26. Which process is common to nearly all living cells?

Answer 25

a.Glycolysis

Question 26

27. All of the reactions of cellular respiration that occur after glycolysis take place in what part of the eukaryotic cell?

Answer 26

C. The mitochondria

Question 27

27. All of the reactions of cellular respiration that occur after glycolysis take place in what part of the eukaryotic cell?

Answer 27

c. the mitochondria

Question 28

Where does the pyruvate oxidation occur?

Answer 28

d. In the mitochondria

Question 29

29. The equation for cellular respiration is: CHOs + 60, 6CO, + 6H20. At what specific point in the cellular respiration process has glucose been broken down completely from a six-carbon molecule to form six molecules of COz

Answer 29

e. After the second oxidation in the citric acid cycle

Question 30

30. What happens to the oxygen that is used in cellular respiration?

Answer 30

d. It is reduced to form water.

Question 31

31. As electrons move along the electron transport chain, they lose potential energy. How is the energy that is released used by the cell?

Answer 31

a. The energy is used to transport protons against their concentration gradient.

Question 32

32. Your friend is having difficulty keeping track of the energy flow from glucose through glycolysis, the citric acid cycle, and electron transport. Your best advice would be to

Answer 32

d. Follow the electrons

Question 33

33. In the absence of oxygen, can cells utilize the electron transport chain?

Answer 33

c.Yes, in the case that a cell can use a terminal electron acceptor other than oxygen, it can make use of the electron transport chain.

Question 34

34. What stage of cellular respiration can occur in human cells with or without oxygen present?

Answer 34

b) Glycolysis

Question 35

35. Regardless of the electron or hydrogen acceptor used, one of the products of fermentation is always

Answer 35

c. NAD+

Question 36

36. When oxygen is unavailable during heavy exercise what process do muscle cells use for energy generation?

Answer 36

d. Glycolysis coupled with lactic acid fermentation

Question 37

37. Carbon dioxide and water can combine to form glucose, water and oxygen. What is required for that process to occur?

Answer 37

c.Light energy from the sun

Question 38

38. Flattened sacs of internal membranes associated with photosynthesis are called

Answer 38

d.Thylakoids

Question 39

39. Inside the chloroplast, where are organic molecules made?

Answer 39

a.Stroma

Question 40

40. In eukaryotes, photosynthesis takes place inside

Answer 40

a.Chloroplasts

Question 41

41. Most atmospheric oxygen comes from photosynthesis. From what molecule is oxygen derived?

Answer 41

(a.) Water

Question 42

42. The aquatic plant Elodea is commonly used to sutyd photosynthesis. You put some Elodea in a test tube filled with water containing radiolabeled oxygen (H °9), shine light on the test tube, and measure the rate of photosynthesis by counting oxygen bubbles released.
    At the end of your experiment, you would find the most 10 in

Answer 42

a. CO2

Question 43

43. In plants, production of NADPH

Answer 43

a. Requires electrons originally found in water.

Question 44

44. A researcher isolates chloroplasts in a tube and illuminates them, but does not provide any carbon dioxide. The chloroplasts will

Answer 44

a. Produce ATP and NADPH, but will not produce glucose.

Question 45

45. Light consists of units of energy called

Answer 45

b. Photons

Question 46

46. What is the color of light that chlorophylls absorb that has the highest energy?

Answer 46

b) Violet-blue

Question 47

47. What are the characteristics of red light, which is absorbed by chlorophylls?

Answer 47

C. its photons have the longest wavelength in the visual spectrum.

Question 48

48. Molecules that absorb light are called

Answer 48

C. Pigments

Question 49

49. Fall leaf color on deciduous trees is a result of

Answer 49

c.) Absence of chlorophyll, which allows the accessory pigments to be revealed.

Question 50

50. Why is eating carrots associated with vision?

Answer 50

b.Carotenoid pigments in carrots are structurally similar to the pigment retinal, used in the vertebrate eye.