Download ANSWERS - Unit 1 Review File

Review for B2, B3 and B4 Test
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What is the function of starch? Storage form of glucose in plants
A starch molecule is a chain of what simple sugar units? glucose
What is the function of glycogen? Storage form of glucose in animals
What process splits polysaccharides into monosaccharides? hydrolysis
The formation of a disaccharide from two monosaccharides is a reaction called dehydration
synthesis.
How does the structure of an unsaturated fatty acid differ from the structure of a saturated fatty acid?
Give an example of each. Unsaturated as carbon to carbon double bonds (e.g oils); saturated
fatty acids do NOT contain double bonds (e.g. fats)
Which type of organism tends to make saturated fatty acids? animals
What property do all lipids share? All have C, H, & O;
Explain the difference between a dipeptide, polypeptide, and a protein. Dipeptide is 2 aa’s; a
polypeptide is many aa’s (polymer of protein); a protein is a macromolecule also made of many
aa’s (usually many polypeptides joined together).
Draw the general formula for an amino acid. H2N-HCO-COOH; or amine-C-carboxylic acid
A peptide bond is always formed between the amine group of one aa and the carboxyl group of the
next.
Using a structural formula diagram, show how a peptide bond is formed between two amino acids.
13. Discuss one type of interaction that can occur between the R groups of an amino acid sequence. Hbonds
14. What makes one amino acid differ from another? The functional or R group
15. What is significant about the R-group in an amino acid? It is what differentiates the aa from another
16. Name three functions of proteins in a living organism. Structural, enzymatic, transport, contraction,
hormonal, & immune functions.
17. Which of these things is not like the others?
a) fibre b) sugar c) starch d) cellulose e) fat
18. Which elements are found in proteins but not in either carbohydrates or lipids. S
19. The basic building blocks for the organic compound:
a) Protein aa b) Triglyceride glycerol & fatty acids c) Carbohydrate monosaccharides d) Nucleic
acids nucleotide
20. What are the three components of the building blocks of nucleic acids? Phosphate, pentose sugar,
nitrogenous base
21. How many nitrogen bases are there? 5 (C, G, A, T, U)
22. A water molecule joins with an adjacent water molecule by forming a(n):
a) ionic bond b) peptide bond c) covalent bond d) hydrogen bond
23. The polarity of a water molecule results from:
a) more of the protons being in the hydrogen nucleus b) more of the electrons being near the hydrogen
nucleus c) the equal numbers of protons in hydrogen and oxygen d) the unequal sharing of electrons
between hydrogen and oxygen
24. Water allows chemical reactions in cells to occur because it:
a) acts as a solvent b) evaporates readily c) is less dense as a solid d) promotes dehydration
synthesis
25. If the pH of a solution changes from 2 to 5, then the solution has:
a) become a base b) lost hydrogen ions c) become more acidic d) gained hydrogen ions.
26. A substance that prevents large changes in the pH of a solution is:
a) DNA b) water c) a buffer d) an enzyme
27. Substances that increase the concentration of hydrogen ions in a solution are:
a) acids b) bases c) enzymes d) polar molecules
28. Blood has a pH that is slightly basic. A sample of blood containing a buffer is treated with a weak acid.
Which pH value would result?
a) 1.57 b) 6.78 c) 7.38 d) 13.21
29. The pH of blood is slightly basic. Which of the following would be the pH of blood?
a) 2.0 b) 6.8 c) 7.4 d) 10.3
30. Which of the following differences between acids and bases is correct?
a) acids are harmful, bases are not b) acids lower the pH, bases raise the pH c) acids release
amino groups, bases release glycerol d) acids release hydroxide ions, bases release hydrogen ions.
31. The process that joins amino acids together to make enzymes is:
a)oxidation b) hydrolysis c)denaturation d) dehydration synthesis
32. Which of the following is an amino (amine) group?
a)NH2 b)OH-1 c) PO4-3 d) COOH
33. The level of protein structure represented by the alpha-helix shape is:
a) primary b) secondary c) tertiary d) quaternary
34. The linear sequence of amino acids found in an enzyme is called its:
a) tertiary structure b) primary structure c) secondary structure d) quaternary structure
35. Proteins may denature when:
a)pH is changed b) oxygen is present c) they form enzymes d) substrate concentration is increased
36. When a protein loses its normal three- dimensional configuration, it is said to be
a) saturated b) denatured c) neutralized d) synthesized
37. A glucose molecule contains:
a)six carbon atoms b) two high-energy phosphates c) three fatty acids and glycerol d) a long chain of
carbohydrate rings
38. The building blocks or monomers that make up carbohydrates are:
a) nucleotides b) amino acids c) monosaccharides d) fatty acids and glycerol
39. Which of the following molecules is a carbohydrate?
a) C3H7O2N b) C6H12O6
c) C13H26O2
d) C20H40O2
40. Glucose in cells is used primarily:
a) as an energy source b) to produce membranes c) to store genetic material d) to produce
enzymes that catalyze reactions.
41. Which of the following is made up of a long chain of glucose molecules?
a) DNA b) starch c) pepsin d) phospholipid
42. The bonding of a glucose molecule and a maltose molecule would result in a:
a) Triglyceride b) disaccharide c) phospholipid d) polysaccharide
43. The hydrolysis of which of the following substances will produce the greatest number of glucose
molecules?
a) maltose b) sucrose c) a disaccharide d) a polysaccharide
44. The main difference between cellulose and starch molecules is:
a) the type of linkage between glucose subunits b) that only cellulose contains ribose building
blocks c) that only starch is made from glucose building blocks d) the type of monosaccharide used to
form these polymers.
45. A characteristic of unsaturated fats is that they:
a) denature as they cool b) are made up of glucose and fructose c) are made up of amino acids and
glycerol d) have double bonds in their carbon chains
46. Which of the following are components of a phospholipid?
a) cholesterol, glycerol, fatty acids b) fatty acids, phosphate group, glycerol c) glycerol, amino
acids, phosphate group d) phosphate group, cholesterol, monosaccharides
47. Compared to saturated fats, unsaturated fats contain less:
a) oxygen b) glycerol c) hydrogen d) fatty acids
48. A lipid molecule is produced when:
a) fatty acids bond to glycerol b) amino acids bond to glycerol c) monosaccharides bond to
glycogen d) dehydration occurs between fatty acids and glycogen
49. An unsaturated fat could be changed into a saturated fat if:
a) peptide bonds were broken b) hydrogen atoms were added c) glycerol molecules were added
d)fatty acid chains were shortened
50. Which of the following types of bonding occurs during complementary base pairing?
a) ionic b) peptide c) covalent
d) hydrogen
51. Energy released from the breakdown of sugar in the cytoplasm is stored in:
a) ATP b) RNA c) DNA d) ADH
52. Which of the following is not a part of a nucleotide?
a) sugar b) glycerol c) phosphate d) nitrogen base
53. Which of the following is composed of nucleotides?
a) fat b) RNA c) starch d) protein
54. In the human body, steroid molecules can act as:
a) buffers b) vacuoles c) hormones d) coenzymes
55. In water, hydrogen bonding occurs between hydrogen in one molecule and:
a) an oxygen atom in the same molecule b) an oxygen atom in a different molecule c) a hydrogen
atom in the same molecule d) a hydrogen atom in a different molecule
56. You can hold a droplet of water on your fingertip. This is an example of: OMIT
a) cohesion of water molecules from hydrogen bonding b) a balance between H+ and OH- ions
c)vibrational movement of the water molecules d) high energy needed to raise the temperature of the
water molecules
57. Hydrogen bonding in water causes water to: OMIT
a) boil at a lower temperature than expected b) be less dense as ice than as liquid water c)absorb
heat with a slight change in temperature d) release heat with a slight change in temperature
+
58. Potassium hydroxide dissociates into K and OH and is therefore a(n):
a) strong acid b) strong base c) litmus test agent d) covalent reaction
59. A genetic mutation can cause a change in the sequence of the 20 amino acids used to build proteins.
Such a change is a change to the proteins:
a) primary structure only b) secondary structure only c) tertiary structure only d) primary structure
but this in turn will likely alter the secondary and tertiary structure as well
60. Glycogen is a:
a) monosaccharide used for quick energy b) polysaccharide used to store energy c) protein found
in cell membranes d) fat found in margarine
61. Maltose is classified as a:
a) nucleic acid b) fatty acid c) protein d) carbohydrate
62. All carbohydrate molecules:
a) contain amino acids b) contain nitrogen and phosphate c) are composed of C, H, and O d)are
composed of C, H, O and N
63. Two glucose molecules can combine to form a disaccharide molecule and
a) another glucose molecule b) another disaccharide molecule c) a dipeptide molecule d)a water
molecule.
64. _______is found in plant cell walls and accounts for their strength.
a) cellulose b) DNA c) glycogen d) starch
65. Hydrolysis of a fat or oil results in the formation of
a) glycerol b) fatty acids c) glucose d) both A and B
66. The functional group found in amino acids that is composed of a nitrogen atom bonded to two hydrogen
atoms is called a(n):
a) amino group b) hydroxyl group c) acid d) R group
67. The figure shown below is:
a) a glucose molecule b) a fatty acid molecule c) a protein molecule d) an amino acid
68. Enzymes are organic compounds classified as:
a) nucleic acids b) carbohydrates c) proteins d) steroids
69. The _____ structure of a protein consists of the sequence of the amino acids joined together by peptide
bonds.
a) primary b) secondary c) tertiary d) quaternary
70. The backbone of a polypeptide could be represented by:
a) N-C-C-N-C-C-N, etc b) the R groups c) nucleotide plus nucleotide plus nucleotide
d)R-C-C-R-C-C-R, etc
71. If two amino acids are joined together, the resulting molecule is a(n)
a) protein b) disaccharide c) fatty acid d) dipeptide
72. Label the following diagram:
Monomers
Hydrolysis
Dehydration
synthesis
water
water
polymers