Chemistry for Changing Times, 14e (Hill/McCreary)
Chapter 16 Biochemistry
16.1 Multiple Choice Questions
1) The substructures that distinguish plant and animal cells are
A) ribosomes.
B) nuclei.
C) mitochondria.
D) chloroplasts.
2) In cells, protein synthesis occurs on the
A) nucleus.
B) mitochondria.
C) ribosomes.
D) cytoplasm.
3) In cells, primary energy production occurs in the
A) mitochondria.
B) nucleus.
C) ribosomes.
D) cell membrane.
4) Cell nutrients and waste must pass through the cell
A) membrane.
B) nucleus.
C) ribosomes.
D) chloroplasts.
5) Chloroplasts in plants convert
A) light energy into heat energy.
B) light energy into electrical energy.
C) light energy into chemical energy.
D) heat energy into chemical energy.
6) The primary chemical for the storage of energy in plants is
A) carbohydrate.
B) protein.
C) cellulose.
D) nucleic acid.
7) The series of chemical reactions that keep living organisms alive is referred to as
A) anabolism.
B) catabolism.
C) biobolism.
D) metabolism.
8) The series of chemical reactions that synthesize molecules for use by a living system is called
A) anabolism.
B) catabolism.
C) biobolism.
D) metabolism.
9) The process in which molecules are degraded to provide energy is known as
A) anabolism.
B) catabolism.
C) energism.
D) metabolism.
10) Which of the following elements is NOT found in carbohydrates?
A) hydrogen
B) oxygen
C) carbon
D) sulfur
11) From an organic chemistry perspective, carbohydrates are polyhydroxy
A) carboxylic acids.
B) aldehydes and ketones.
C) amines.
D) amino acids.
12) Which of the following is a monosaccharide?
A) fructose
B) sucrose
C) starch
D) amylose
13) The polysaccharide that is in potatoes and cereal grains is
A) starch.
B) galactose.
C) cellulose.
D) fructose.
14) Which of the following is a polysaccharide?
A) erythrulose
B) fructose
C) starch
D) maltose
15) The monomer unit in amylopectin is ________.
A) glucose
B) mannose
C) lactose
D) sucrose
16) Animal starch is called
A) amylose.
B) amylopectin.
C) cellulose.
D) glycogen.
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17) An example of a disaccharide is
A) sucrose.
B) galactose.
C) dextrose.
D) cellulose.
18) The name carbohydrate reflects
A) the ratio of carbon to hydrogen in the molecule.
B) the ratio of carbonyl groups to total carbon content.
C) the ratio of carbon to the combined ratio of “hydrogen to oxygen.”
D) the ratio of carbon to oxygen.
19) The molecular formula for glucose is
A) C12H6O6.
B) C6H12O6.
C) C6H6O12.
D) C12H22O11.
20) Which of the following polymers is NOT made by plants?
A) amylopectin
B) amylose
C) cellulose
D) glycogen
21) Unsaturated fats are often liquids called
A) hydrogenated fats.
B) oils.
C) triglycerides.
D) glycerol.
22) A fatty acid is determined to have 12 carbon atoms. This fatty acid is probably from a(n)
A) synthetic source.
B) natural source.
C) plant.
D) animal.
23) Iodine number is a measure of
A) the number of iodine atoms in a carbohydrate.
B) the number of iodine atoms in a fat.
C) the number of iodine atoms in a protein.
D) the degree of unsaturation of a fat.
24) Fats and oils are examples of
A) ketones.
B) aldehydes.
C) alcohols.
D) esters.
25) Fats and oils are differentiated from each other on the basis of their
A) melting points.
B) densities.
C) glycerol content.
D) boiling points.
26) Triglyceride is another term for
A) cholesterol.
B) protein.
C) blood sugar.
D) a fat or oil.
27) Animal fats are
A) solids and have a smaller proportion of unsaturated fats.
B) solids and have a higher proportion of unsaturated fats.
C) liquids and have a higher proportion of unsaturated fats.
D) liquids and have a smaller proportion of unsaturated fats.
28) The iodine numbers for several samples of fatty acids are shown below. Which fatty acid is the most
saturated?
A) 40 (Fatty Acid A)
B) 80 (Fatty Acid B)
C) 105 (Fatty Acid C)
D) 135 (Fatty Acid D)
29) A compound that has two fatty acids joined to a glycerol molecule by ester linkages is a(n)
A) diglyceride.
B) fat.
C) oil.
D) triglyceride.
30) Which of the following would have the lowest iodine number?
A) butter
B) corn oil
C) peanut oil
D) sunflower oil
31) The mass of iodine that is consumed by 100 g of a fat or oil is known as the
A) fat replacement number.
B) iodine number.
C) oil replacement number.
D) saturation number.
32) What functional group(s) is (are) contained in an amino acid?
A) –NH2
B) –C=O
C) -COOH
D) both –NH2 and -COOH
33) What is a zwitterion?
A) a compound that carries two positively charged atoms
B) a compound that carries two negatively charged atoms
C) a compound that carries either two positively charged atoms or two negatively charged atoms
D) a compound that carries one positively charged atom and one negatively charged atom
34) Which of the following statements about essential amino acids is NOT correct?
A) Essential amino acids cannot be synthesized by the human body.
B) Essential amino acids cannot be incorporated into protein.
C) Essential amino acids must be part of the diet.
D) Some amino acids are essential for infants and children, but not for adults.
35) The materials used in biochemical production of molecules
A) tend to be toxic, even at low concentrations.
B) are difficult to degrade.
C) work well under mild temperature conditions.
D) result in large amounts of waste being produced.
36) Using biochemical methods to make products has many advantages over more traditional methods.
Which of the following is NOT an advantage of biochemical methods?
A) Reactions frequently use water as a solvent, and water is nontoxic and nonflammable.
B) Nonpolar products are difficult to separate from a water solvent.
C) Most biochemical reactions are carried out at mild temperatures and atmospheric pressure.
D) Enzymes can be used repeatedly to catalyze the formation of many molecules and thus generate little
waste.
37) Which of the following approaches has NOT been explored as an alternate source of gasoline?
A) Transformation of plant carbohydrates to form gasoline.
B) Engineering bacteria that can convert carbohydrates and carbon dioxide into gasoline.
C) Development of bacteria that produce hydrocarbon fuels.
D) All of the above have been explored as alternate sources of gasoline.
38) Proteins are
A) polyamides.
B) polysaccharides.
C) polysulfides.
D) polyamines.
39) The bond between two amino acids is called a peptide bond. What type of bond is a peptide bond?
A) amide
B) anhydride
C) amine
D) glyceride
40) How many different tripeptides can be made that contain serine, glycine and phenylalanine?
A) 1
B) 2
C) 3
D) 6
41) A relatively small molecule with more than 10 amino acids is called a
A) polypeptide.
B) protein.
C) polysaccharide.
D) polynucleic acid.
42) The primary structure of a protein is determined by
A) the amino acid composition.
B) the order of amino acids in the protein.
C) the hydrogen bonding that gives the protein three dimensional shape.
D) the intertwining of protein molecules to form a “functional” protein.
43) The secondary structure of a protein is determined by
A) the amino acid composition.
B) the order of amino acids in the protein.
C) the hydrogen bonding between atoms in peptide bonds that gives the protein a three dimensional
shape.
D) the intertwining of protein molecules to form a “functional” protein.
44) The helical structure of certain proteins, such as wool, is part of the protein’s
A) primary structure.
B) secondary structure.
C) tertiary structure.
D) quaternary structure.
45) The pleated structure of certain proteins, such as silk, is part of the protein’s
A) primary structure.
B) secondary structure.
C) tertiary structure.
D) quaternary structure.
46) Disulfide linkages in proteins are formed when two units of ________ are oxidized to form a covalent
bond.
A) valine
B) threonine
C) cysteine
D) asparagine
47) A disulfide linkage in a protein is a(n)
A) ionic bond between sulfur atoms on different amino acids.
B) covalent bond between sulfur atoms on different amino acids.
C) hydrogen bond between sulfur atoms on different amino acids.
D) hydrophobic interaction between sulfur atoms on different amino acids.
48) Certain side chains (R groups) in amino acids are nonpolar. In the structure of a protein, nonpolar
groups are generally found
A) on the interior of the protein structure, shielded from interaction with water molecules.
B) on the exterior of the protein structure, shielded from interaction with water molecules.
C) on the interior of the protein structure, maximizing their interaction with water molecules.
D) on the exterior of the protein structure, maximizing their interaction with water molecules.
49) An alpha helix contains
A) intramolecular hydrogen bonding.
B) intermolecular hydrogen bonding.
C) ester formation within the chain.
D) ether formation within the chain.
50) A beta pleated sheet
A) contains ester bonds between chains.
B) contains hydrogen bonding between chains.
C) contains amide bonds between chains.
D) contains ether bonds between chains.
51) Which of the following forces is NOT involved in the determining the structure of proteins?
A) base pairing
B) disulfide linkages
C) dispersion forces
D) hydrogen bonds
52) The interactions between different chains in a protein contribute to its ________ structure.
A) primary
B) quaternary
C) secondary
D) tertiary
53) Which of the following is NOT involved in determining the tertiary structure of a protein?
A) ester bonds
B) salt bridges
C) disulfide linkages
D) hydrogen bonds
54) Which of the following involves the formation of a covalent bond?
A) dispersion forces
B) disulfide linkages
C) hydrogen bonding
D) salt bridges
55) A coenzyme may be an ion such as
A) Mg2+.
B) Cl–.
C) O2-.
D) K+.
56) Extremophiles are microorganisms that
A) live in harsh environments that would kill other creatures.
B) live outside the body.
C) live in the water supply.
D) live in thick forests.
57) Enzymes are
A) catalysts.
B) structural material.
C) genetic material.
D) nucleic acids.
58) Which of the following statements BEST describes the action of enzymes in living systems? A specific
enzyme generally catalyzes
A) one specific reaction.
B) a group of similar reactions.
C) many different reactions.
D) either one specific reaction or a group of similar reactions.
59) The portion of an enzyme where the substrate “fits” during the reaction is called the
A) active site.
B) action site.
C) reaction site.
D) substrate site.
60) An organic molecule that must bind to an enzyme to make it function properly is a(n)
A) apoenzyme.
B) coenzyme.
C) extremophile.
D) isomerase.
61) A substance that is acted upon by an enzyme and undergoes a change is knows as a(n)
A) cofactor.
B) coenzyme.
C) essential amino acid.
D) substrate.