Name _______________________
Date __________________________
Biology I:Chapter 3 Test, Organic Compounds
True/False
Indicate whether the sentence or statement is true or false.
____
1. Adhesion is an attraction between different substances.
____
2. The ability of water to retain heat helps cells maintain homeostasis.
____
3. (lab)Nonpolar molecules dissolve well in water.
____
4. (lab) Water molecules attract nonpolar molecules such as oil.
____
5. Your body cannot adjust the pH of body fluids.
____
6. Organic compounds contain carbon atoms that are covalently bonded to other elements—typically hydrogen,
oxygen, and other carbon atoms.
____
7. A nucleotide has four parts.
____
8. DNA stores hereditary information that can be used to make proteins.
____
9. Hydrolysis reactions produce polymers and water.
Multiple Choice
Identify the letter of the choice that best completes the statement or answers the question.
____ 10. When placed in the same container, oil and water do not mix because
a. they are both polar. b. water is polar and oil is nonpolar. c. they are both nonpolar. d. water is nonpolar
and oil is polar.
____ 11. Water is a polar molecule because
a. it contains two hydrogen atoms for each oxygen atom. b. it has a charge. c. different parts of the
molecule have slightly different charges. d. it does not have a charge.
____ 12. Due to the polarity of water, compounds that dissolve best in water contain
a. nonpolar bonds. b. ionic bonds. c. polar bonds. d. Both (b) and (c)
____ 13. Acidic solutions have a pH that is
a. less than 7. b. between 7 and 14. c. a negative number. d. more than 7.
____ 14. Hydrogen ions, H+, react with hydroxide ions, OH–, to form
a. water. b. an acid. c. a base. d. None of the above
____ 15. Which of the following is not an organic compound?
a. carbohydrate b. ice c. lipid d. nucleic acid
____ 16. All organic compounds contain the element
a. carbon. b. nitrogen. c. calcium. d. sodium.
____ 17. Which of the following is a carbohydrate?
a. DNA b. insulin c. wax d. sucrose
____ 18. Which organic molecules below are classified as carbohydrates?
a. amino acids b. fatty acids c. nucleotides d. sugars
____ 19. Animals store glucose in the form of
a. cellulose. b. glycogen. c. wax. d. lipids.
____ 20. Carbohydrates and lipids have many carbon-hydrogen bonds; therefore, they both
a. store energy in these bonds. b. are easily dissolved in water. c. dissolve only in vinegar. d. exist only in
cells of plants.
Molecule A
Molecule B
____ 21. Refer to the illustration above. Molecules like Molecule B are found in
a. carbohydrates. b. lipids. c. nucleic acids. d. proteins.
____ 22. Polysaccharides are
a. carbohydrates. b. lipids. c. proteins. d. unsaturated fats.
____ 23. Lipids are
a. polar molecules. b. similar to water molecules. c. water soluble. d. nonpolar molecules.
____ 24. Which organic molecules below are most closely related to proteins?
a. amino acids b. fatty acids c. nucleotides d. sugars
____ 25. Long chains of amino acids are found in
a. carbohydrates. b. lipids. c. proteins. d. sugars.
____ 26. All of the following are examples of lipids except
a. saturated fats. b. starch. c. cholesterol. d. earwax.
____ 27. Liquid fats called oils contain
a. mostly unsaturated fatty acids. b. mostly saturated fatty acids. c. many glucose molecules. d. amino
acids.
____ 28. Lipids are soluble in
a. water. b. salt water. c. oil. d. All of the above
____ 29. Which organic molecules below are most closely related to lipids?
a. amino acids b. fatty acids c. nucleotides d. sugars
____ 30. The shape of a protein is primarily determined by
a. the type and sequence of its amino acids. b. its size. c. its cell location. d. None of the above
____ 31. Which organic molecules below are most closely related to nucleic acids?
a. amino acids b. fatty acids c. nucleotides d. sugars
____ 32. The two types of nucleic acids are
a. chlorophyll and retinal. b. DNA and RNA. c. lipids and sugars. d. glucose and glycogen.
____ 33. DNA stores
a. fat. b. carbohydrates. c. protein. d. heredity information.
____ 34. If the pH of stomach acid and of oven cleaner were measured,
a. both would be below 7. b. both would be above 7. c. the pH of stomach acid would be above 7, but the
pH of oven cleaner would be below 7. d. the pH of stomach acid would be below 7, but the pH of oven
cleaner would be above 7.
____ 35. Amino acid is to protein as
a. fat is to lipid. b. DNA is to RNA. c. sugar is to fat. d. simple sugar is to starch.
Short Answer
36. What are the four groups of organic compounds found in living things?
Essay (Worth 5 points each) Please write your answer in complete sentences.
37. Compare and contrast adhesion and cohesion, using capillary action as an example.
38. When working in the laboratory, you discover that the solutions you are working with are tomato juice with a
pH of 4 and soap with a pH of 10. By comparing the pH of these substances with that of pure water, would
you find that these substances are acidic or basic? Explain.
Other
USING SCIENCE SKILLS
pH Values of Some Common Substances
Substance
pH
hydrochloric acid
1.0
sulfuric acid
tomatoes
1.2
4.2
rainwater
6.2
pure water
7.0
sea water
ammonium chloride
8.5
11.1
sodium hydroxide
13.0
Figure 2-2
39. Applying Concepts According to the pH values of Figure 2-2, does a solution with a hydrogen ion
concentration less than that of pure water have a pH greater or less than 7?
40. Calculating A change of one unit on the pH scale represents a tenfold increase in the concentration of
hydrogen ions. According to the pH values listed in Figure 2-2, how much greater is the hydrogen ion
concentration in tomatoes than in rainwater?
Biology I:Chapter 3 Test, Organic Compounds
Answer Section
TRUE/FALSE
1.
2.
3.
4.
5.
6.
7.
8.
9.
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
T
T
F
F
F
T
F
T
F
MULTIPLE CHOICE
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
B
C
D
A
A
B
A
D
D
B
A
B
A
D
A
C
B
A
C
B
A
C
B
D
D
D
SHORT ANSWER
36. ANS:
The four groups are carbohydrates, lipids, nucleic acids, and proteins.
ESSAY
37. ANS:
Both adhesion and cohesion are attractions. They are different in that adhesion is the force of attraction
between the molecules of two different substances, whereas cohesion is the force of attraction between
molecules of the same substance. Possible examples include capillary action, in which the adhesion between
water and glass causes the water to rise in a narrow tube against the force of gravity. Because of hydrogen
bonding, water is extremely cohesive. This causes molecules on the surface of water to be drawn inward,
which is why drops of water form beads on smooth surfaces.
38. ANS:
The pH of pure water is 7, or neutral. Tomato juice, with a pH of 4, contains higher concentrations of H+ ions
than pure water and is an acidic solution. Soap, with a pH of 10, contains lower concentrations of H+ ions than
pure water and is a basic solution.
OTHER
39. ANS:
greater
40. ANS:
100 times (10  10)