Pathophysiology Exam 1

An ordered photographic display of a set of chromosomes from a single cell is a(n): A) metaphase spread. B) autosomal spread. C) karyotype. D) anaphase spread. - answerc An error in which homologous chromosomes fail to separate during meiosis is termed: A) aneuploidy. B) nondisjunction. C) polyploidy. D) anaplasia. - answerb A somatic cell that does not contain a multiple of 23 chromosomes is called: A) an aneuploid cell. B) a euploid cell. C) a polyploidy cell. D) a haploid cell. - answera A 20-year-old pregnant female gives birth to a stillborn child. Autopsy reveals that the fetus has 92 chromosomes. Which of the following describes this condition? A) Euploidy B) Triploidy C) Tetraploidy D) Aneuploidy - answerc If a person is a chromosomal mosaic, the person may: A) be a carrier of the genetic disease. B) have a mild form of the genetic disease. C) have two genetic diseases. D) be sterile as a result of the genetic disease. - answerb The most common cause of Down syndrome is: A) paternal nondisjunction. B) maternal translocations. C) maternal nondisjunction. D) paternal translocations. - answerc Risk factors for Down syndrome include: 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. - answerd A 13-year-old girl has a karyotype that reveals an absent homologous X chromosome with only a single X chromosome present. Her condition is called: A) Down syndrome. B) Cri du chat syndrome. C) Turner syndrome. D) Edward syndrome - answerc A child is diagnosed with cystic fibrosis. History reveals that the child's parents are first cousins. Cystic fibrosis was most likely the result of: A) X inactivation. B) genomic imprinting. C) consanguinity. D) obligate carriers. - answerc Joey, age 9, is admitted to a pediatric unit with Duchenne muscular dystrophy. He inherited this condition through a: A) sex-linked dominant trait. B) sex-influenced trait. C) sex-limited trait. D) sex-linked recessive trait. - answerd A 50-year-old male was recently diagnosed with Huntington disease. Transmission of this disease is associated with: A) penetrance. B) recurrence risk. C) expressivity. D) delayed age of onset. - answerd People who have neurofibromatosis will show varying degrees of the disease; this is because of the genetic principle of: A) penetrance. B) expressivity. C) dominance. D) recessiveness. - answerb Cystic fibrosis is caused by an _____ gene. A) X-linked dominant B) X-linked recessive C) autosomal dominant D) autosomal recessive - answerd To express a polygenic trait: A) genes must interact with the environment. B) several genes must act together. C) multiple mutations must occur in the same family. D) in situ cloning must occur. - answerb The gradual increase in height among the human population over the past 100 years is an example of: A) polygenic trait. B) multifactorial trait. C) crossing over. D) recombination. - answerb A couple has three offspring: one child with an autosomal dominant disease trait and two who are normal. The father is affected by the autosomal dominant disease, but the mother does not have the disease gene. What is the recurrence risk of this autosomal dominant disease for their next child? A) 50% B) 33% C) 25% D) Impossible to determine - answera A 12-year-old male is diagnosed with Klinefelter syndrome. His karyotype would reveal which of the following? A) XY B) XX C) XYY D) XXY - answerd A 5-year-old male presents with mental retardation and is diagnosed with Fragile X syndrome. Which of the following is most likely to cause this syndrome? A) Translocation B) Inversion C) Nondisjunction D) Duplication at fragile sites - answerd The outward manifestation of a disease, often influenced by both genes and the environment, is called the disease: A) genotype. B) allele. C) phenotype. D) dominance. - answerc Which of the following genetic diseases manifests with progressive dementia in middle to later adulthood? A) Duchenne muscular dystrophy B) Cystic fibrosis C) Achondroplasia D) Huntington disease - answerd Which of the following types of genetic disorders is the most common cause of miscarriage? A) Autosomal dominant B) Autosomal recessive C) X-linked recessive D) Chromosomal - answerd Which of the following is an accurate characteristic of an autosomal recessive pedigree? A) On average, 50% of the children will have the autosomal recessive disease if one parent has the disease. B) Males are affected more than females. C) On average, 25% of the children are affected by the autosomal recessive disease if both parents are carriers. D) There is a decreased risk of disease with consanguinity. - answerc Which of the following is an accurate characterization of an X-linked recessive pedigree?