- Chapter 5-The Structure and Function of Large Biological Molecules
1) Which of these classes of biological molecules does NOT include polymers?
A) lipids
B) carbohydrates
C) proteins
D) nucleic acids
Answer: A
2) Which of the following is NOT a polymer?
A) glucose
B) starch
C) cellulose
D) DNA
Answer: A
3) How many molecules of water are used to completely hydrolyze a polymer that is 11 monomers long?
A) 12
B) 11
C) 10
D) 9
Answer: C
4) Which of the following best summarizes the relationship between dehydration reactions and hydrolysis?
A) Dehydration reactions assemble polymers; hydrolysis reactions break polymers apa
B) Dehydration reactions eliminate water from membranes; hydrolysis reactions add water to membrane
C) Dehydration reactions and hydrolysis reactions assemble polymers from monomer
D) Hydrolysis reactions create polymers and dehydration reactions create monomers.
Answer: A
5) The molecular formula for glucose is C6H12O6. What would be the molecular formula for a molecule made by linking three glucose molecules together by dehydration reactions?
A) C18H36O18
B) C18H32O16
C) C6H10O5
D) C18H30O15
Answer: B
6) What is the difference between an aldose sugar and a ketose sugar?
A) the number of carbons
B) the position of the hydroxyl groups
C) the position of the carbonyl group
D) One is a ring form, the other is a linear chain
Answer: C
7) What is the major structural difference between starch and glycogen?
A) the types of monosaccharide subunits in the molecules
B) the type of glycosidic linkages in the molecule
C) whether glucose is in the α or β form
D) the amount of branching that occurs in the molecule
Answer: D
8) Which polysaccharide is an important component in the structure of many animals and fungi?
A) chitin
B) cellulose
C) amylopectin
D) amylose
Answer: A
9) What does the term insoluble fiber refer to on food packages?
A) cellulose
B) polypeptides
C) starch
D) amylopectin
Answer: A
10) A molecule with the chemical formula C6H12O6 is probably a .
A) fatty acid
B) polysaccharide
C) nucleic acid
D) monosaccharide
Answer: D
11) Lactose, a sugar in milk, is composed of one glucose molecule joined by a glycosidic linkage to one galactose molecule. How is lactose classified?
A) as a hexose
B) as a monosaccharide
C) as a disaccharide
D) as a polysaccharide
Answer: C
12) Starch and cellulose .
A) are polymers of glucose
B) are cis-trans isomers of each other
C) are used for energy storage in plants
D) are structural components of the plant cell wall
Answer: A
13) Humans can digest starch but not cellulose because .
A) humans have enzymes that can hydrolyze the α-glycosidic linkages of starch but not the β- glycosidic linkages of cellulose
B) starch monomers are joined by covalent bonds and cellulose monomers are joined by ionic bonds
C) the monomer of starch is glucose, while the monomer of cellulose is galactose
D) the monomer of starch is fructose, while the monomer of cellulose is glucose
Answer: A
14) The molecule shown in the accompanying figure is .
A) a hexose
B) a pentose
C) fructose
D) maltose
Answer: A
15) A glycosidic linkage is analogous to which of the following in proteins?
A) an amino group
B) a peptide bond
C) a disulfide bond
D) a β-pleated sheet
Answer: B
16) Cooking oil and gasoline (a hydrocarbon) are not amphipathic molecules because they .
A) do not have a polar or charged region
B) do not have a nonpolar region
C) have hydrophobic and hydrophilic regions
D) are highly reduced molecules
Answer: A
17) How do phospholipids interact with water molecules?
A) The polar heads avoid water; the nonpolar tails attract water (because water is polar and opposites attract).
B) Phospholipids do not interact with water because water is polar and lipids are nonpolar.
C) The polar heads interact with water; the nonpolar tails do not.
D) Phospholipids dissolve in water
Answer: C
18) Phospholipids and triglycerides both .
A) contain serine or some other organic compound
B) have three fatty acids
C) have a glycerol backbone
D) have a phosphate
Answer: C
19) Which of the following is the best explanation for why vegetable oil is a liquid at room temperature while animal fats are solid?
A) Vegetable oil has more double bonds than animal fats
B) Vegetable oil has fewer double bonds than animal fats.
C) Animal fats have no amphipathic character.
D) Vegetable oil has longer fatty-acid tails than animal fats have. Answer: A
20) Which of the following statements is FALSE? Saturated fats .
A) are more common in animals than in plants
B) have many double bonds in the carbon chains of their fatty acids
C) usually solidify at room temperature
D) contain more hydrogen than unsaturated fats that consist of the same number of carbon atoms
Answer: B
D) Denatured (unfolded) proteins do not function normally.
Answer: D