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| 1 | |
Which one of the following statements about mutations is incorrect? |
| | A) | Mutations can be passed from parent cell to daughter cell, or from parent to offspring. |
| | B) | By definition, all mutations exhibit negative consequences on the cell(s) that acquire them. |
| | C) | Cancer can arise from uncorrected mutational events. |
| | D) | All species have multiple systems in place to correct mutations that occur. |
| | E) | All of the statements about mutations are correct. |
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| 2 | |
Which of the following is a method of DNA repair utilized to correct a base mismatch? |
| | A) | Methyl-directed mismatch repair |
| | B) | Direct repair |
| | C) | Nucleotide excision repair |
| | D) | Methyl-directed mismatch repair and nucleotide excision repair |
| | E) | Methyl-directed mismatch repair, direct repair, and nucleotide excision repair |
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| 3 | |
Which of the following is/are ways that cancer may originate? |
| | A) | A single cell that losing regulatory control over cell division. |
| | B) | Exposure to carcinogens. |
| | C) | An inherited predisposition. |
| | D) | Gene mutation. |
| | E) | All of the choices are ways that cancer may originate |
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| 4 | |
Which one of the following is not an example of a point mutation? |
| | A) | A change in one coding specifying valine to a different codon specifying valine |
| | B) | An insertion of a single extra base during DNA replication |
| | C) | A change in a methionine codon to a codon specifying isoleucine |
| | D) | An insertion of a transposon into the coding region of a structural gene |
| | E) | A change in a tryptophan codon to a stop codon |
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| 5 | |
Sickle cell anemia is characterized by which of the following types of mutations? |
| | A) | Missense |
| | B) | Nonsense |
| | C) | Frameshift |
| | D) | Same sense |
| | E) | Insertion |
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| 6 | |
Which of the following most accurately describes the phenotypic effect of a mutation in the E. coli lac operator sequence that prevents lac repressor protein from binding? |
| | A) | Beta-galactosidase would be expressed only in the presence of lactose and the absence of glucose. |
| | B) | Lactose would not be efficiently transported into the cell. |
| | C) | Beta-galactosidase would be expressed even in the absence of lactose. |
| | D) | Beta-galactosidase would be expressed only in the presence of lactose and the presence of glucose. |
| | E) | None of the choices describe the effect of the described mutation in the lac operator region. |
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| 7 | |
True or False: The Lederberg experiment demonstrated that physiological events determine if traits will be passed from parent to offspring. |
| | A) | True |
| | B) | False |
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| 8 | |
Somatic cells that are genetically different from other regions of somatic cells in the same organism is most accurately referred to as a |
| | A) | mutant. |
| | B) | hybrid. |
| | C) | heterozygote. |
| | D) | genetic mosaic. |
| | E) | carrier. |
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| 9 | |
Which of the following causes of mutation would be an example of an induced mutation? |
| | A) | Spontaneous deamination of cytosine into thymine |
| | B) | An incorrect base incorporated and not corrected during DNA replication |
| | C) | Free radicals in the cell alter the structure of DNA and interfere with normal replication |
| | D) | Exposure to X-ray irradiation |
| | E) | Incorporation of transposon DNA into the genome |
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| 10 | |
Which of the following most accurately describes the damage typically caused by ultraviolet radiation? |
| | A) | A thymine is converted to a guanine and base pairs with cytosine instead of adenine. |
| | B) | Free radicals from the high intensity radiation cause a double stranded break in the DNA. |
| | C) | Instead of an adenine-thymine base pair, an unusual thymine-thymine base pair forms. |
| | D) | Irradiation with ultraviolet light causes the loss of several nucleotides in the affected region of DNA. |
| | E) | Adjacent thymine bases in a strand of DNA nucleotides become covalently linked to each other. |
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| 11 | |
True or False: Using the Ames test, a compound is determined to be mutagenic if it causes a His- bacterial strain (requires histidine in the growth medium) to become His+(does not require supplemental histidine) at a greater rate than spontaneous mutation by itself. |
| | A) | True |
| | B) | False |
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| 12 | |
Leukemia |
| | A) | is caused by a defect in the mismatch repair system. |
| | B) | typically results in base substitution mutations. |
| | C) | can be caused by gene amplification of a proto-oncogene. |
| | D) | results when an individual does not spend enough time outside. |
| | E) | can be corrected by a direct repair mechanism. |
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| 13 | |
Proto- oncogenes ___________________________ and oncogenes _____________________. |
| | A) | amplify cell growth : repress cell growth |
| | B) | repress cell growth : amplify cell growth |
| | C) | are precursors to oncogenes : abnormally amplify cell growth |
| | D) | abnormally amplify cell growth : are the precursors to proto-oncogenes |
| | E) | promote tumors growth : cause benign tumors to become malignant. |
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| 14 | |
Which of the following DNA Repair mechanisms are mutated and therefore non-functional in individuals with Xeroderma pigmentosum, PIBIDS and Cockayne's syndrome? |
| | A) | Nucleotide excision repair |
| | B) | Direct Repair |
| | C) | Methyl-directed mismatch repair |
| | D) | Base excision repair |
| | E) | Direct repair and methyl-directed mismatch repair |
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| 15 | |
True or False: Loss-of-function mutations in proto-oncogenes promote cancer. |
| | A) | True |
| | B) | False |
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| 16 | |
Which of the following prevents the proper function of tumor suppressor genes by blocking activation of a promoter region? |
| | A) | Chromosome loss |
| | B) | Gene mutations |
| | C) | DNA methylation |
| | D) | Chromosome loss and DNA methylation |
| | E) | Chromosome loss, gene mutations, and DNA methylation |
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| 17 | |
Which one of the following genetic changes can convert a proto-oncogene into an oncogene? |
| | A) | Gene amplification |
| | B) | Chromosomal translocation |
| | C) | missense mutation |
| | D) | Retroviral insertion |
| | E) | All of these genetic changes can convert a proto-oncogene into an oncogene. |
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| 18 | |
True or False: Tumor suppressor genes are responsible for maintaining cell integrity. |
| | A) | True |
| | B) | False |
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| 19 | |
True or False: A sarcoma is a cancerous tumor found in connective tissue or bone. |
| | A) | True |
| | B) | False |
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| 20 | |
When p53 is activated, a cell cannot progress |
| | A) | through M-phase. |
| | B) | from G2 into M-phase. |
| | C) | from G1 into S-phase. |
| | D) | through S-phase. |
| | E) | from S-phase into G2. |
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