Genetics Chapter 25

True or False: a genetic disease is spread to individuals sharing similar environmental situations.

False

True or False: Identical twins share a genetic disease more often than fraternal twins.

True

True or False: comparing someone with a genetic disease to another person in the general population, the person with the disease is more likely to have a family member with the same disease.

True

Genetic testing is used to determine whether a(n) ___________ has a disease-causing gene, while genetic screening is used to determine how frequently the gene is found in a(n) ____________. a. group of patients; individual b. population; individual c. individual; population

c. individual; population

Chromosomal abnormalities related to genetic diseases can be detected by _____________. a. assaying for enzyme activity b. using a Western blot c. producing a karyotype d. DNA microarray analysis

c. producing a karyotype

Select human diseases that are inherited in an X-linked recessive fashion. a. Hemophilia A b. Androgen insensitivity syndrome c. Familial hypercholesteromia d. Duchenne muscular dystrophy

a. Hemophilia A b. Androgen insensitivity syndrome d. Duchenne muscular dystophy

A method for obtaining fetal cells in a sample of the fluid surrounding the fetus is called ______________. a. amniocentesis b. alpha fetoprotein sampling c. chorionic villus sampling d. ultrasound

a. amniocentesis

Select the human disorders that are inherited in an autosomal recessive fashion. a. Phenylketonuria b. Sickle cell disease c. Cystic fibrosis d. Huntington disease

a. Phenylketonuria b. Sickle cell disease c. Cystic fibrosis

Select human disorders that are inherited in an X-linked dominant manner. a. Vitamin-D resistant rickets b. Rett syndrome c. Incontinentia pigmenti d. Cystic fibrosis

a. Vitamin-D resistant rickets b. Rett syndrome c. Incontinentia pigmenti

In one study, autism showed 60% concordance for monozygotic twins and 0% concordance for dizygotic twins. This demonstrates that autism is ______________. a. a genetic disease b. caused by factors affecting fetal development c. caused by environmental factors affecting people in the same family

a. a genetic disease

The abnormal form of a prion protein causes a neurodegenerative disease by ______________. a. catalyzing the conversion of the normal protein form to the abnormal form b. replicating the highest numbers that crowd out the normal form of the protein c. destroying copies of the normal form of the protein

a. catalyzing the conversion of the normal protein form to the abnormal form

A dominant genetic disorder can be caused by ___________, a situation where one functional copy of an allele is not sufficient to produce a normal phenotype. a. haploinsufficiency b. gain-of-function mutation c. dominant-negative mutation

a. haploinsufficiency

Which type of catalytic activity occurs in prion-caused disease? a. the abnormal form of the prion protein catalyzes a reaction that converts normal protein to misfolded ones b. the normal form of the prion protein catalyzes the digestion of the other properly-folded normal proteins. c. the normal form of the prion protein catalyzes a reaction that converts other normal proteins to misfolded ones. d. the abnormal form of the prion protein catalyzes the digestion of the properly-folded normal proteins

a. the abnormal form of the prion protein catalyzes a reaction that converts normal protein to misfolded ones

Marfan syndrome, which is inherited in an autosomal dominant manner, is caused by a mutation in the gene for ____________. a. LDL receptor b. Pax6 transcription factor c. fibroblast growth factor receptor-3 d. fibrillin-1

d. fibrillin-1

Personalized medicine can be used to select a _________________. (multiple answers) a. therapy b. preventative medicine c. medication d. health care provider

a. therapy b. preventative medicine c. medication

What tool do scientists use to follow a human pattern of inheritance from generation to generation? a. PCR b. Pedigree analysis c. Genetic crosses d. Western blotting

b. Pedigree analysis

When a defect in a single gene causes a human disease, the mutant gene often follows ___________. a. complex inheritance patterns that cannot be easily studied b. simple Mendelian inheritance patterns c. epigenetic inheritance patterns

b. simple Mendelian inheritance patterns

Dizygotic twins _______________. a. share an average of 50% of the same alleles b. arose from one egg, fertilized by one sperm, Into a group of cells that separated during embryonic development c. share 100% of the same alleles

a. share an average of 50% of the same alleles

How can abnormal forms of the prion protein arise within an individual? (multiple answers) a. Certain drugs cause the conversion of the normal form of the prion protein to the abnormal one. b. A person can be infected by eating meat from an animal with the disease c. A person may have inherited an allele that causes their normal prion protein to convert to an abnormal one at a low rate. d. Diets high in saturated fat stimulate the conversion of normal prion proteins to abnormal ones.

b. A person can be infected by eating meat from an animal with the disease c. A person may have inherited an allele that causes their normal prion protein to convert to an abnormal one at a low rate.

What is the inheritance pattern when a trait occurs with the same frequency in both sexes and an affected offspring can have two unaffected parents? a. X-linked recessive b. Autosomal recessive c. Autosomal dominant d. X-linked dominant

b. Autosomal recessive

Which methods can be used at the DNA level to test for specific mutations related to a genetic disease? (multiple answers) a. western blot b. DNA microarray analysis c. DNA sequencing d. enzyme activity assay e. Fluorescence in situ hybridization (FISH)

b. DNA microarray analysis c. DNA sequencing e. Fluorescence in situ hybridization

Which method can be used at the DNA level to detect the presence of a specific mutation in a disease-causing allele? a. enzyme activity array b. western blot c. DNA microarray analysis

c. DNA microarray analysis

What is the inheritance pattern for a trait that occurs with the same frequency in both sexes and two affected heterozygous individuals have, on average, 25% unaffected offspring? a. X-linked dominant b. X-linked recessive c. Autosomal recessive d. Autosomal dominant

d. Autosomal dominant

What is the inheritance pattern when the trait occurs with the same frequency in both sexes and two unaffected heterozygotes have, on average, 25% affected children? a. X-linked dominant b. Autosomal dominant c. X-linked recessive d. Autosomal recessive

d. Autosomal recessive

The disease hemophilia is caused by a deficiency in any one of three blood clotting factors. Two of these factors are encoded by genes on the X chromosome and the other clotting factor gene is located on an autosome. Since mutations in more than one gene can cause hemophilia, this represents ______________. a. locus heterogeneity b. locus heterozygosity c. pleiotropy d. a linkage abnormality

a. locus heterogeneity

Twins that are genetically identical to each other are called __________ twins. a. monozygotic b. fraternal c. dizygotic

a. monozygotic

A disease-causing agent made only of protein is called a ____________. a. prion b. bacteriophage c. virus d. bacterium

a. prion

A dominant genetic disorder can be caused by a ____________ mutation, where the product of an altered gene gains a new or abnormal function. a. haploinsufficient b. gain-of-function c. dominant-negative d. loss-of-function

b. gain-of-function

Suppose a disease-causing allele shows autosomal recessive inheritance. How could a carrier of this disease-causing allele be identified? a. carriers show the same phenotype as individuals with the homozygous recessive genotype. b. carriers have a reduction in the amount of DNA present in the region containing the allele. c. carriers often show reduced activity for the enzyme encoded by the allele

c. carriers often show reduced activity for the enzyme encoded by the allele

In vitro fertilization is a procedure in which _______________. a. donor eggs and sperm are transferred to mother's fallopian tube b. eggs are transferred to the mother's uterus c. sperm and egg are combined outside of the mother's body

c. sperm and egg are combined outside of the mother's body

Which of these is a common example of widespread genetic screening of newborns to identify certain disorders? a. amniocentesis and karyotyping b. enzyme assay for Gaucher disease carrier status c. test for excess phenylalanine indicating phenylketonuria (PKU) d. enzyme assay for Tay-Sachs allele carrier status

c. test for excess phenylalanine indicating phenylketonuria (PKU)

What is the inheritance pattern for a trait that more commonly affects males than females and can often be observed in brothers or fathers of a woman who has affected sons? a. Autosomal dominant b. Autosomal recessive c. X-linked dominant d. X-linked recessive

d. X-linked recessive

A small portion of the fetal part of the placenta is removed to prepare a karyotype in the process called _______________. a. ultrasound b. amniocentesis c. alpha fetoprotein sampling d. chorionic villus sampling

d. chorionic villus sampling

Preimplantation genetic diagnosis is a method testing for genetic diseases in ____________. a. newborn babies that may have metabolic defects b. adults that are carriers of single-gene defects c. fetuses that may have chromosomal abnormalities d. embryos produced by in vitro fertilization

d. embryos produced by in vitro fertilization