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Multiple Response
Identify one or more choices that best complete the statement or answer the question.
____
1. Which functional group is not present in this molecule?
a.
b.
c.
d.
e.
____
carboxyl
methyl
hydroxyl
amino
a-d are not present
2. Three or four of the following illustrations depict different structural isomers of the organic
compound with molecular formula C6H14. For clarity, only the carbon skeletons are shown;
hydrogen atoms that would be attached to the carbons have been omitted. Which one, if any, is NOT
a structural isomer of this compound?
a.
c.
b.
d.
e. Each of the illustrations in the other answer choices depicts a structural isomer of
the compound with molecular formula C6H14.
____
3. A compound contains hydroxyl groups as its predominant functional group. Which of the following
statements is true concerning this compound?
a. It lacks a hydrogen, so it acts as an acid.
b. It should dissolve in water.
c. It should dissolve in a nonpolar solvent.
d. It won't form hydrogen bonds with water.
e. It is hydrophobic.
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____
4. Which of the following contains nitrogen in addition to carbon, oxygen, and hydrogen?
a. an alcohol such as ethanol
b. a monosaccharide such as glucose
c. a steroid such as testosterone
d. an amino acid such as glycine
e. a hydrocarbon such as methane
____
5. Which two functional groups are always found in amino acids?
a. ketone and aldehyde
b. carbonyl and carboxyl
c. carboxyl and amino
d. phosphate and sulfhydryl
e. hydroxyl and aldehyde
____
6. A carbon skeleton is covalently bonded to both an amino group, a carboxyl group and a methyl.
When placed in water it
a. would function only as an acid because of the carboxyl group.
b. would function only as a base because of the amino group.
c. would function as neither an acid nor a base, but would be hydrophilic due to the
methyl.
d. would function as both an acid and a base, but would be hydrophobic due to the
methyl.
e. is impossible to determine how it would function.
Figure 4.5
____
7. Based on Figure 4.5 - Which of the structures is an impossible covalently bonded molecule?
a. A
b. B
c. C
d. D
e. E
____
8. Testosterone and estrogen are
a. hydrophilic.
b. carbohydrates.
c. proteins.
d. phospholipids.
e. steroids.
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____
9. Testosterone and estradiol are male and female sex hormones, respectively, in many vertebrates. In
what way(s) do these molecules differ from each other?
a. Testosterone and estrogen are structural isomers but have the same molecular
formula.
b. Testosterone and estrogen are geometric isomers but have the same molecular
formula.
c. Testosterone and estrogen have different functional groups attached to the same
carbon skeleton.
d. Testosterone and estrogen have distinctly different chemical structures, with one
including four fused rings of carbon atoms, while the other has three rings.
e. Testosterone and estrogen are isomers of the same organic molecule.
____ 10. How many molecules of water are needed to completely hydrolyze a polymer that is 11 monomers
long?
a. 12
b. 11
c. 10
d. 9
e. 8
____ 11. Which of the following best summarizes the relationship between dehydration reactions and
hydrolysis?
a. Dehydration reactions assemble polymers, and hydrolysis reactions break down
polymers.
b. Macromolecular synthesis occurs through the removal of water and digestion
occurs through the addition of water.
c. Dehydration reactions can occur only after hydrolysis.
d. Hydrolysis creates monomers, and dehydration reactions break down polymers.
e. A and B are correct.
____ 12. On food packages, to what does the term "insoluble fiber" refer?
a. cellulose
b. polypeptides
c. starch
d. saturated fats
e. proteins
Figure 5.1
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____ 13. If 2 molecules of the general type shown in Figure 5.1 were linked together, carbon 1 of one
molecule to carbon 4 of the other, the single molecule that would result would be
a. maltose.
b. fructose.
c. glucose.
d. cellulose
e. sucrose.
____ 14. Which of the following is true regarding starch and cellulose?
a. They are both polymers of glucose.
b. They are not isomers of one another.
c. They can both be digested by humans.
d. They are both used for energy storage in plants.
e. They are both structural components of the plant cell wall.
____ 15. All of the following statements concerning saturated fats are true except
a. They are more common in animals than in plants.
b. They have multiple double bonds in the carbon chains of their fatty acids.
c. They generally solidify at room temperature.
d. They contain more hydrogen than unsaturated fats having the same number of
carbon atoms.
e. They are one of several factors that contribute to heart disease.
____ 16. A molecule with the formula C18H54O2 is probably a
a. carbohydrate.
b. fatty acid.
c. protein.
d. glycerol
e. hydrocarbon.
____ 17. Which of the following statements is false for the class of biological molecules known as lipids?
a. They are soluble in water.
b. They are an important constituent of cell membranes.
c. They contain more energy than proteins and carbohydrates.
d. They are not true polymers.
e. They contain hormones and cholesterol.
____ 18. Which of the following is true regarding saturated fatty acids?
a. They are the predominant fatty acid in corn oil.
b. They have double bonds between carbon atoms of the fatty acids.
c. They are the principal molecules in lard and butter.
d. They are usually liquid at room temperature.
e. They are usually produced by plants.
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____ 19. Large organic molecules are usually assembled by polymerization of a few kinds of simple subunits.
Which of the following is an exception to this statement?
a. a steroid
b. cellulose
c. hemoglobin in a blood cell
d. an enzyme
e. myoglobin in a muscle
____ 20. Why are human sex hormones considered to be lipids?
a. They are essential components of cell membranes.
b. They are steroids, which are not soluble in water.
c. They are made of fatty acids.
d. They are hydrophilic compounds.
e. They contribute to cardiac disease.
____ 21. The bonding of two amino acid molecules to form a larger molecule requires which of the
following?
a. removal of a water molecule
b. addition of a water molecule
c. formation of an ionic bond
d. formation of a hydrogen bond
e. both A and C
____ 22. Which bonds are created during the formation of the primary structure of a protein?
a. peptide bonds
b. hydrogen bonds
c. disulfide bonds
d. phosphodiester bonds
e. A, B, and C
____ 23. The alpha helix and the beta pleated sheet are both common polypeptide forms found in which level
of protein structure?
a. primary
b. secondary
c. tertiary
d. quaternary
e. all of the above
____ 24. The tertiary structure of a protein is the
a. bonding together of several polypeptide chains by weak bonds.
b. order in which amino acids are joined in a polypeptide chain.
c. unique three-dimensional shape of the fully folded polypeptide.
d. organization of a polypeptide chain into an alpha helix or beta pleated sheet.
e. overall protein structure resulting from the aggregation of two or more polypeptide
subunits.
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____ 25. Functioning enzymes are
a. polysaccharides
b. lipids
c. quarternary proteins
d. polypeptides
e. secondary proteins
____ 26. Which term includes all others in the list?
a. monosaccharide
b. disaccharide
c. starch
d. carbohydrate
e. polysaccharide
____ 27. Sucrose is a disaccharide, composed of the monosaccharides glucose and fructose. The hydrolysis of
sucrose by the enzyme sucrase results in
a. bringing glucose and fructose together to form sucrose.
b. the release of water from sucrose as the bond between glucose and fructose is
broken.
c. breaking the bond between glucose and fructose and forming new bonds from the
atoms of water.
d. production of water from the sugar as bonds are broken between the glucose
monomers.
e. utilization of water as a covalent bond is formed between glucose and fructose to
form sucrase.
____ 28. Which of the following statements regarding enzymes is true?
a. Enzymes increase the energy required for a chemical reaction.
b. Enzymes increase the rate of a reaction.
c. Enzymes change the direction of chemical reactions.
d. Enzymes are permanently altered by the reactions they catalyze.
e. Enzymes prevent changes in substrate concentrations.
____ 29. The active site of an enzyme is the region that
a. maintains the induced fit in extreme pH environments
b. is involved in the catalytic reaction of the enzyme.
c. binds the products of the catalytic reaction by absorbing water
d. adds water to the substrate during dehydration synthesis
e. both c and d
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Refer to Figure 8.1 to answer the following questions.
Figure 8.1
____ 30. Which curve represents the behavior of an enzyme taken from a bacterium that lives in hot springs at
temperatures of 70°C or higher?
a. curve 1
b. curve 2
c. curve 3
d. curve 4
e. curve 5
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Practice Biochem Test
Answer Section
MULTIPLE RESPONSE
1. ANS: B
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