1. Chapter 2 Holt McDougal Biology
Biology Review
Chapter 2
Holt McDougal Biology

2. Question 1 A substance composed of only 1 type of atom is called what?
A) a cell
B) a nucleus
C) a molecule
D) an element .

3. Answer 1
D- Element

4. Q 2
T or F: Enzymes are specific for specific substrates. .

5. A 2
TRUE

6. Q 3
3) List the 2 types of Nucleic Acids

7. A 3
DNA & RNA

8. Q 4
4) True or False: “Nonpolar molecules have no negative or positive poles.

9. A 4
TRUE

10. Q 5 5) An enzyme or catalyst does what to the reaction rate?
A) speeds it up
B) Slows it down
C) has no effect

11. A 5
A- speeds it up.

12. Q 6
6) A __________________molecule has a slightly positive end and a slightly negative end.

13. A 6
6) A ___POLAR_____molecule has a slightly positive end and a slightly negative end.

14. Q 7
7) List some conditions that affect the function of enzymes?

15. A 7
Temperature, pH, amount of substrate

16. Q 8
8) What is meant by saying that an enzyme is DENATURED? What might cause this?

17. A 8 - this means the enzyme is destroyed. Caused by high temperatures.
8) What is meant by saying that an enzyme is DENATURED? What might cause this?
- this means the enzyme is destroyed. Caused by high temperatures.

18. Q 9
9) How do enzymes work to speed up a reaction?

19. A 9
Enzymes LOWER the ACTIVATION ENERGY needed to start the reaction.

20. Q 10
10) T or F: “An Enzyme is not used up when catalyzing a reaction.”

21. A 10
True

22. Q 11
11) The molecule on which an enzyme acts is called a(n) ____________.

23. A 11
11) The molecule on which an enzyme acts is called a(n) substrate

24. Q 12
12) The portion of an enzyme molecule into which a specific substrate can fit is called the _________________________.

25. A 12
12) The portion of an enzyme molecule into which a specific substrate can fit is called the active site

26. Q 13
13) Are lipids (fats) polar or nonpolar?

27. A 13
Nonpolar

28. Q 14 14) In a solution, the substances are ________________.
A) Evenly distributed
B) unevenly distributed

29. A 14
A) Evenly distributed

30. Q 15
15) When sugar is dissolved in water, the water acts as the _____________.
A) Solute
B) Solvent
C) Ion

31. A 15
B) Solvent

32. Q 16
16) Long chains of __________ ____________ form the building blocks of proteins.

33. A 16
16) Long chains of amino acids_ form the building blocks of proteins.

34. Q 17
17) Are sugars considered a Carbohydrate, Protein, Lipid, or Nucleic Acid?

35. A 17
Sugars are a carbohydrate.

36. Q 18
18) _______solutions have a pH of less than 7.

37. A 18
18) Acidic solutions have a pH of less than 7.

38. Q 19
19) The pH scale ranges from ____ to ______.

39. A 19
19) The pH scale ranges from __0__ to 14

40. Q 20
20) All organic compounds contain what element?

41. A 20
CARBON

42. Q 21
21) T or F: “Carbohydrates, lipids, and nucleic acids are all organic macromolecules.”

43. A 21
TRUE

44. Q 22
22) Why don’t oil & water mix when placed in the same container?

45. A 22
Water is polar & oil is nonpolar so they don’t mix.

46. Q 23 23) The bond formed when 2 atoms SHARE
a pair of electrons is called a(n) __________bond.

47. A 23 23) The bond formed when 2 atoms SHARE
a pair of electrons is called a(n) covalent bond

48. Q 24
24) A molecule with a partial positive charge on one side & partial negative charge on the other side such as water said to be a ___________________molecule.

49. A 24
24) A molecule with a partial positive charge on one side & partial negative charge on the other side such as water said to be a POLAR molecule.

50. Q 25 _________bonds form between molecules that have opposite charges.
A) Ionic B) Covalent C) hydrogen

51. A 25
A) Ionic

52. Q 26
26) Is starch a lipid, carbohydrate, or protein?

53. A 26
carbohydrate

54. Q 27 27) A substance with a pH greater than 7 is _____________.
A) Acidic B) Basic C) Neutral

55. A 27
B) Basic

56. Q 28 28) Long chains of nucleotides make up _________________.
A) Amino Acids
B) Nucleic Acids
C) Protiens
D) Lipids
E) Carbohydrates

57. A 28
B) Nucleic Acids

58. Q 29
29) Weak chemical attractions between polar molecules of water are __________bonds.
A) Hydrogen
B) Nuceleotide
C) Peptide
D) Ionic

59. A 29
A) Hydrogen

60. Q 30
30) The attraction between like water molecules to other water molecules is called __________________.

61. A 30
30) The attraction between like water molecules to other water molecules is called cohesion

62. Q31
31) The attraction of water molecules to different molecules is called ____________.

63. A 31
31) The attraction of water molecules to different molecules is called Adhesion.

64. Q 32 (25)
What is an element?

65. A 32 (25)
Element = a pure substance composed of only 1 type of atom.

66. Q 33 (26)
26 (1) ______are typically liquids called oils at room temp.

67. A 33
(1) U (unsaturated fats) are typically liquids called oils at room temp.

68. Q 34
2) ______are typically solids at room temp.

69. A 34
2) saturated fats are typically solids at room temp Amino Acids

70. Q 35
_____typically come from animal sources and are less healthy to consume.

71. A 35
3) Saturated fats typically come from animal sources and are less healthy to consume.

72. Q 36
4) ______typically come from plant sources & are considered “more healthy” to consume.

73. A 36
4) UNSATURATED FATS typically come from plant sources & are considered “more healthy” to consume.

74. Q 37
5) ________have only single bonds (NO DOUBLE BONDS) and therefore have the maximum number of hydrogens possible for the molecule.

75. A 37
5) saturated fats have only single bonds (NO DOUBLE BONDS) and therefore have the maximum number of hydrogens possible for the molecule.

76. Q 38
6) _______contain double bonds so they have fewer hydrogens.

77. A 38
6) Unsaturated fats contain double bonds so they have fewer hydrogens.

78. Q 39
Which reaction pathway most likely occurred in the presence of a catalyst or enzyme? How do you know?

79. A 39
Which reaction pathway most likely occurred in the presence of a catalyst or enzyme? How do you know?
-reaction 2 (because the line is lower on the graph, so it takes less activation energy to start the reaction).

80. Q 40
The difference between the 2 paths shown is due to a difference in the _________ _______ needed to start each reaction.

81. A 40
The difference between the 2 paths shown is due to a difference in the activation energy needed to start each reaction.

82. Q 41 (bonus question)
Which of the following conditions affects the function of enzymes?
A) Concentration
B) Heat
C) pH
D) All of the above
E) None of the above

83. A 41
D) All of above

84. Q 42 (Bonus)
________, such as glucose, are a source of energy, and are used as structural materials in organisms.
A) Carbohydrates
B) Proteins
C) Lipids
D) Nucleic Acids

85. A 42
A) Carbohydrates

86. Q 43 (BONUS)
___________are nonpolar molecules that store energy & are an important part of cell membranes.
A) Carbohydrates
B) Protiens
C) Lipids
D) Nucleic Acids

87. A 43
C-Lipids