Quiz 2: Genes and Genetic Diseases

A nurse recalls that the basic components of DNA are: A) pentose sugars and four phosphate bases. B) a phosphate molecule, deoxyribose, and four nitrogenous bases. C) adenine, guanine, and purine. D) codons, oxygen, and cytosine.

Which of the following mutations have the most significant effect on protein synthesis? A) Base pair substitutions B) Silent mutations C) Intron mutations D) Frameshift mutations

The base components of DNA are: A) A, G, C, and U. B) P, G, C, and T. C) A, G, C, and T. D) X, XX, XY, and YY.

A DNA strand has a region with the sequence ATCGGAT. Which of the following would be a complementary strand? A) CGATACGT B) TAGCCTAG C) TUGCCTUG D) UAGCCUAG

A biologist is explaining how RNA directs the synthesis of protein. Which process is the biologist describing? A) Termination B) Transcription C) Translocation D) Translation

What is the result of homologous chromosomes failing to separate during meiosis? A) Neurofibromatosis B) Aneuploidy C) Polyploidy D) Conjoined twins

A cell that does not contain a multiple of 23 chromosomes is called a _____ cell. A) diploid B) euploid C) polyploid D) haploid

A 20-year-old pregnant female gives birth to a stillborn child. Autopsy reveals that the fetus has 92 chromosomes. What term may be on the autopsy report to describe this condition? A) Biploidy B) Triploidy C) Tetraploidy D) Aneuploidy

The condition in which an extra portion of a chromosome is present in each cell is called: A) reciprocal translocation. B) partial trisomy. C) inversion. D) Down syndrome.

After a geneticist talks to a patient about being a chromosomal mosaic, the patient asks the nurse what that means. What should the nurse say? A) "You are only be a carrier of the genetic disease." B) "You have a mild form of the genetic disease." C) "You have two genetic diseases." D) "The expression of your DNA has been altered, causing a genetic disease."

What is the most common cause of Down syndrome? A) Paternal nondisjunction B) Maternal translocations C) Maternal nondisjunction D) Paternal translocations

What is a risk factor for Down syndrome? A) Fetal exposure to mutagens in the uterus B) Increased paternal age C) Family history of Down syndrome D) Pregnancy in women over age 35

A 13-year-old girl has a karyotype that reveals an absent homologous X chromosome with only a single X chromosome present. What medical diagnosis will the nurse observe on the chart? A) Down syndrome B) cri du chat syndrome C) Turner's syndrome D) Fragile X syndrome

What genetic disorder is the result if an individual possesses an XXY chromosome configuration? A) Turner's syndrome B) Klinefelter's syndrome C) Down syndrome D) Fragile X syndrome

A patient demonstrates severe intellectual disability caused by a deletion of part of chromosome 5. What genetic disorder will the nurse see documented in the chart? A) Prader-Willi syndrome B) Down syndrome C) cri du chat syndrome D) Trisomy X

An aide asks the nurse why people who have neurofibromatosis show varying degrees of the disease. Which genetic principle should the nurse explain to the aide? A) Penetrance B) Expressivity C) Dominance D) Recessiveness

What gene abnormality causes cystic fibrosis? A) X-linked dominant B) X-linked recessive C) Autosomal dominant D) Autosomal recessive

A 15-year-old female is diagnosed with Prader-Willi syndrome. What is this condition an example of? A) Genomic imprinting B) An autosomal recessive trait C) An autosomal dominant trait D) A sex-linked trait

A patient, age 9, is admitted to a pediatric unit with Duchenne muscular dystrophy. When planning care, the nurse recalls that the patient inherited this condition through a trait that is: A) X-linked dominant. B) X-influenced. C) X-limited. D) X-linked recessive.

A child is diagnosed with cystic fibrosis. History reveals that the child's parents are siblings. Cystic fibrosis was most likely the result of: A) X-inactivation. B) genomic imprinting. C) consanguinity. D) obligate carriers.

A 12-year-old male is diagnosed with Klinefelter's syndrome. His karyotype would reveal which of the following? A) XY B) XX C) XYY D) XXY

What is needed for a polygenic trait to be expressed? A) Genes must interact with the environment. B) Several genes must act together. C) Multiple mutations must occur in the same family. D) Penetrance must occur.

A 13-year-old female has a karyotype that reveals an absent homologous X chromosome with only a single X chromosome present. Her features include a short stature, widely spaced nipples, and a reduced carrying angle at the elbow. What is her diagnosis? A) Down syndrome B) cri du chat syndrome C) Turner's syndrome D) Klinefelter's syndrome

The gradual increase in height among the human population over the past 100 years is an example of: A) a polygenic trait. B) a multifactorial trait. C) crossing over. D) recombination.

When discussing DNA replication, which enzyme is most important? A) RNA polymerase B) Transfer RNA C) Messenger RNA D) DNA polymerase

What regions of RNA must be spliced out for functional mRNA to be formed? A) Promoter sites B) Introns C) Exons D) Anticodons

A 50-year-old male was recently diagnosed with Huntington's disease. What is a key feature of this condition? A) Penetrance of a trait B) Recurrence risk C) Expressivity D) Delayed age of onset

What type of mutation does not change the amino acid sequence and thus has no observable consequence? A) Frameshift B) Spontaneous C) Silent D) Missense

A nurse is reviewing the pedigree chart. When checking for a proband, what is the nurse looking for? A) The person who is first diagnosed with a genetic disease B) The individual who has a disease gene but is phenotypically normal C) The phenotype of genetic material D) The codominance

Which one of the following disorders is manifested primarily in males? A) Cystic fibrosis B) Neurofibromatosis C) Muscular dystrophy D) Down syndrome

When the nurse is teaching the staff about X-linked recessive disorders, which information should the nurse include? (Select all that apply.) A) The trait is seen much more often in females than in males. B) The trait is never transmitted from father to son. C) The gene can be transmitted through a series of carrier females. D) The gene is passed from an affected father to all his daughters. E) The trait never skips generations.