32) Polysaccharides, triacylglycerides, and proteins are similar in that they
A) are synthesized from monomers by the process of hydrolysis.
B) are synthesized from subunits by dehydration reactions.
C) are synthesized as a result of peptide bond formation between monomers.
D) are decomposed into their subunits by dehydration reactions.
E) all contain nitrogen in their monomer building blocks.
Answer: B
Topic: Concepts 5.1-5.4
Skill: Application/Analysis

33) Dehydration reactions are used in forming which of the following compounds?
A) triacylglycerides
B) polysaccharides
C) proteins
D) triacylglycerides and proteins only
E) triacylglycerides, polysaccharides, and proteins
Answer: E
Topic: Concepts 5.1-5.4
Skill: Knowledge/Comprehension

41) The amino acids of the protein keratin are arranged predominantly in an α helix. This secondary structure is stabilized by
A) covalent bonds.
B) peptide bonds.
C) ionic bonds.
D) polar bonds.
E) hydrogen bonds.
Answer: E
Topic: Concept 5.4
Skill: Knowledge/Comprehension

46) Misfolding of polypeptides is a serious problem in cells. Which of the following diseases are associated with an accumulation of misfolded polypeptides?
A) Alzheimer's only
B) Parkinson's only
C) diabetes mellitus only
D) Alzheimer's and Parkinson's only
E) Alzheimer's, Parkinson's, and diabetes mellitus
Answer: D
Topic: Concept 5.4
Skill: Knowledge/Comprehension
47) Changing a single amino acid in a protein consisting of 325 amino acids would
A) alter the primary structure of the protein, but not its tertiary structure or function.
B) cause the tertiary structure of the protein to unfold.
C) always alter the biological activity or function of the protein.
D) always alter the primary structure of the protein and disrupt its biological activity.
E) always alter the primary structure of the protein, sometimes alter the tertiary structure of the protein, and affect its biological activity.
Answer: E
Topic: Concept 5.4
Skill: Application/Analysis

57) If 14C-labeled uridine triphosphate is added to the growth medium of cells, what macromolecules will be labeled?
A) phospholipids
B) DNA
C) RNA
D) both DNA and RNA
E) proteins
Answer: C
Topic: Concept 5.5
Skill: Application/Analysis

69) If cells are grown in a medium containing radioactive 32P-labeled phosphate, which of these molecules will be labeled?
A) phospholipids
B) nucleic acids
C) proteins
D) amylose
E) both phospholipids and nucleic acids
Answer: E
Topic: Concepts 5.2-5.5
Skill: Application/Analysis

75) Which of the following statements is true regarding the molecule illustrated in Figure 5.2?
A) It is a saturated fatty acid.
B) A diet rich in this molecule may contribute to atherosclerosis.
C) Molecules of this type are usually liquid at room temperature.
D) It is a saturated fatty acid and a diet rich in this molecule may contribute to atherosclerosis.
E) It is a saturated fatty acid, a diet rich in this molecule may contribute to atherosclerosis, and molecules of this type are usually liquid at room temperature.
Answer: D
Topic: Concept 5.3
Skill: Knowledge/Comprehension

1) The element present in all organic molecules is
A) hydrogen.
B) oxygen.
C) carbon.
D) nitrogen.
E) phosphorus.
Answer: C
Topic: Concept 4.1
Skill: Knowledge/Comprehension

2) The complexity and variety of organic molecules is due to
A) the chemical versatility of carbon atoms.
B) the variety of rare elements in organic molecules.
C) the fact that they can be synthesized only in living organisms.
D) their interaction with water.
E) their tremendously large sizes.
Answer: A
Topic: Concept 4.1
Skill: Knowledge/Comprehension

3) The experimental approach taken in current biological investigations presumes that
A) simple organic compounds can be synthesized in the laboratory from inorganic precursors, but complex organic compounds like carbohydrates and proteins can only be synthesized by living organisms.
B) a life force ultimately controls the activities of