Test Bank to accompany Life: The Science of Biology, Eleventh Edition Sadava • Hillis • Heller • Hacker Chapter 15: Gene Mutation and Molecular Medicine

Test Bank to accompany Life: The Science of Biology, Eleventh Edition Sadava • Hillis • Heller • Hacker Chapter 15: Gene Mutation and Molecular Medicine TEST BANK QUESTIONS Multiple Choice 1. Sequencing of a child’s genomic DNA reveals that the child is a heterozygote for a new mutation. This mutation appears in all of the cells tested from a variety of tissues (including skin, blood, and hair). The mutation is not found in either the mother or the father. Most likely, this is a new mutation that occurred in . a. somatic; one of the parents b. somatic; the child c. germ line; one of the parents d. germ line; both of the parents e. germ line; the child 2. People are often more concerned about germ line mutations than somatic ones because germ line mutations a. have phenotypic effects, whereas somatic mutations do not. b. affect more nucleotides than somatic mutations do. c. transitions, whereas somatic mutations are transversions. d. are transmitted to offspring, whereas somatic mutations are not. e. occur more frequently than somatic mutations. 3. One son of Great Britain’s Queen Victoria was born with the X-linked disease hemophilia, and two of her daughters were carriers, as some of their male children were born with hemophilia. King Albert did not have hemophilia, nor did any of Queen Victoria’s relatives on her mother’s side. Based on this information, the hemophilia mutation most likely originated a. as a somatic mutation in Queen Victoria. b. in a sperm cell from King Albert. c. as a somatic mutation in King Albert. d. in the egg from Queen Victoria’s mother. e. in the egg from King Albert’s mother. 4. Gain of function mutations a. are dominant mutations that are expressed in wild-type cells. b. are dominant mutations that are expressed in mutant cells. c. are the cause of continuous division in cancer cells. d. can be analyzed only under restrictive conditions. e. are expressed only with the appropriate environmental signals. Learning Outcome: 15.1.1.b Identify examples of the following types of mutations: silent, loss-of-function, gain-of-function, conditional, and reversion. Bloom’s Level: 1. Remembering 5. If a mutation has a visible effect at 26°C, but no visible effect at 20°C, then 20°C is the temperature and 26°C is the temperature. a. permissive; conditional b. permissive; restrictive c. restrictive; conditional d. restrictive; permissive e. conditional; restrictive 6. Because of the redundancy in the genetic code, many mutations in the coding regions of genes are a. transitions. b. transversions. c. inversions. d. somatic mutations. e. silent mutations. 7. The isoenzyme hexosaminidase A (HEXA), composed of subunits α and β, breaks down molecules containing terminal N-acetyl hexosamines. Tay-Sachs disease is caused by a recessively inherited mutation in the gene coding for the α subunit, which is the subunit that hydrolyzes the lipid GM2 ganglioside. Accumulation of this lipid in the brain leads to progressive deterioration of the nervous system and death, usually by age 4. A child born homozygous for the loss-of-function α subunit allele nevertheless does not develop Tay-Sachs disease. Sequence analysis of the β subunit alleles reveals that one allele has a mutation that makes it able to hydrolyze GM2 ganglioside. This is a - of-function mutation, which is most likely . a. gain; dominant b. gain; recessive c. loss; dominant d. loss; recessive e. loss; intermediately dominant 8. Refer to the table. Alkaptonuria is an inborn error of metabolism, caused by defects in an enzyme in the pathway that breaks down tyrosine (see Section 14.1). Humans who are homozygous for one of these mutations make nonfunctional enzyme and accumulate the enzyme’s substrate, homogentisic acid, which causes their disease symptoms. In 1996, researchers in Spain cloned and sequenced the gene for the enzyme and characterized several mutant alleles. The table shows the wild-type coding strand sequence for part of the gene and the corresponding region from one of the mutant alleles. What type of mutation is this? a. Silent b. Nonsense c. Frame-shift d. Missense e. Reversion 9. Refer to the following image. Given the codon UCA in the first exon of a gene, which change is most likely to result in a nonsense mutation? a. Change of nucleotide in the first position b. Change of nucleotide in the second position c. Change of nucleotide in the third position d. A transversion of A to U e. A transition of A to G 10. Suppose that for a certain gene, nearly 100 percent of the normal level of expression is required to produce the normal phenotype. Based on this requirement, one could predict that a mutation would be . a. gain of function; recessive b. loss of function; dominant c. loss of function; recessive d. nonsense; recessive e. loss of function; a conditional mutation 11. Drosophila melanogaster flies that have the Shaker mutation appear normal at room temperature. If you hold a vial of flies with this mutation for a few minutes (i.e., warm the vial to body temperature, or 37oC), the flies become uncoordinated because of the warmth of your hand. If you remove your hand, the flies soon recover. Based on this information, which statement about the Shaker mutation must be true? a. It is permissive at 37oC. b. It is a reversion mutation. c. It improves flight at temperatures lower than 37oC. d. It is a recessive mutation. e. It is restrictive at 37oC. Learning Outcome: 15.1.2.a Use a defined DNA sequence to illustrate how the following occur and describe their effect upon phenotype: transitions, transversions, missense mutations, nonsense mutations, frame-shift mutations, and mutations outside the coding region of a gene. Bloom’s Level: 5. Evaluating 12. Suppose that a mutation appears in a small population of plants that changes the color of their seeds from yellow to green. This mutation reaches 100 percent frequency in the population. Many generations later, some individuals with yellow seeds are found. We can definitely say that these individuals have acquired a(n) a. inversion. b. transition. c. reversion mutation. d. conditional mutation. e. somatic mutation. Learning Outcome: 15.1.2.a Use a defined DNA sequence to illustrate how the following occur and describe their effect upon phenotype: transitions, transversions, missense mutations, nonsense mutations, frame-shift mutations, and mutations outside the coding region of a gene. Bloom’s Level: 2. Understanding 13. Which statement about mutations is true? a. All point mutations are transitions. b. All transitions are point mutations. c. All point mutations are base substitutions. d. All point mutations are nonsense mutations. e. All point mutations are missense mutations. Learning Outcome: 15.1.2.a Use a defined DNA sequence to illustrate how the following occur and describe their effect upon phenotype: transitions, transversions, missense mutations, nonsense mutations, frame-shift mutations, and mutations outside the coding region of a gene. Bloom’s Level: 4. Analyzing 14. A bacterial cell has been exposed to a powerful mutagen. The chromosomal sequences of the ancestral cell and the descendant cell are shown. (The ellipses represent intervening sequences that are identical.) Based on this information, there have been transitions and transversions. a. 0; 5 b. 2; 3 c. 2; 5 d. 3; 2 e. 3; 3 Learning Outcome: 15.1.2.a Use a defined DNA sequence to illustrate how the following occur and describe their effect upon phenotype: transitions, transversions, missense mutations, nonsense mutations, frame-shift mutations, and mutations outside the coding region of a gene. Bloom’s Level: 3. Applying 15. Which mutation is least likely to be a frame-shift mutation? a. An insertion of six nucleotides b. A deletion of four nucleotides c. An insertion of two nucleotides d. A deletion of eight nucleotides e. An insertion of ten nucleotides Learning Outcome: 15.1.2.a Use a defined DNA sequence to illustrate how the following occur and describe their effect upon phenotype: transitions, transversions, missense mutations, nonsense mutations, frame-shift mutations, and mutations outside the coding region of a gene. Bloom’s Level: 4. Analyzing 16. Analysis of the abnormal white blood cells of a patient with leukemia, a type of cancer, reveals that a protein, termed LP, is always functionally active. In normal white blood cells this protein is found to be only functionally active in response to growth stimuli that induce cell division. Surprisingly, sequencing of leukemic cell DNA shows that both LP alleles in the patient’s leukemic cells are normal. However, the DNA sequencing also reveals that both alleles of protein ILP, which normally inhibits LP activity in the absence of growth stimuli, have each acquired a mutation. Further research proves that these mutations in both ILP alleles are the reason why LP is always active and, consequently, induces the leukemic cells to constantly undergo cell division. a. loss-of-function b. gain-of-function c. silent d. reversion e. conditional Learning Outcome: 15.1.2.a Use a defined DNA sequence to illustrate how the following occur and describe their effect upon phenotype: transitions, transversions, missense mutations, nonsense mutations, frame-shift mutations, and mutations outside the coding region of a gene. Bloom’s Level: 4. Analyzing 17. Suppose that in one cell in your skin, chromosome 14 and chromosome 18 exchange genetic materials. This change is inherited by subsequent cells. This is an example of a mutation that is also a(n) . a. germ line; inversion b. germ line; point mutation c. germ line; translocation d. somatic; inversion e. somatic; translocation ...............................................continued...................................................