Deck 4: Genes and Genetic Diseases

Question 1

The purpose of a staining technique of chromosomes such as Giemsa is to:

A)allow the mitotic process to be followed and monitored for variations.
B)allow the numbering of chromosomes and identification of variations.
C)identify new somatic cells formed through mitosis and cytokinesis.
D)distinguish the sex chromosome from the homologous chromosomes.

Answer 1

allow the numbering of chromosomes and identification of variations.

Question 2

The key to accurate DNA replication is complementary base pairing.

Answer 2

True

Question 3

An amniocentesis is recommended for pregnant women who:

A)have a history of chronic illness.
B)have a family history of genetic disorders.
C)are older than 40 years of age.
D)had a late menarche.

Answer 3

have a family history of genetic disorders.

Question 4

What is the diagnosis of a 13-year-old female who has a karyotype that reveals an absent homologous X chromosome with only a single X chromosome present with features that include a short stature, widely spaced nipples, reduced carrying angle at the elbow, and sparse body hair?

A)Down syndrome
B)Cri du chat syndrome
C)Turner syndrome
D)Klinefelter syndrome

Question 5

Chromosome abnormalities are the leading cause of mental retardation and miscarriage.

Question 6

Which clinical manifestations would be expected for a child who has complete trisomy of the twenty-first chromosome?

A)Widely spaced nipples, reduced carrying angle at the elbow, and sparse body hair
B)An IQ of 25 to 70, low nasal bridge, protruding tongue, and flat, low-set ears
C)High-pitched voice, tall stature, gynecomastia, and an IQ of 60 to 90
D)Circumoral cyanosis, edema of the feet, short stature, and mental slowness

Question 7

DNA directs the synthesis of all of the body's proteins.

Question 8

Inserting bone marrow cells into an individual who produces abnormal erythrocytes is an example of _____ therapy.

A)somatic cell
B)germ cell
C)genetic engineering
D)recombinant DNA

Question 9

The most clinically useful technique for prenatal diagnosis of chromosomal abnormalities at 3 months' gestation is:

A)gene mapping.
B)linkage analysis.
C)amniocentesis.
D)chorionic villus sampling.

Question 10

Transcription is best defined as a process by which:

A)DNA polymerase binds to the promoter site on RNA.
B)RNA directs the synthesis of polypeptides for protein synthesis.
C)RNA is synthesized from a DNA template.
D)a base pair substitution results in a mutation of the amino acid sequence.

Question 11

RNA polymerase is the most important protein in DNA replication.

Question 12

An amniocentesis indicates a neural tube defect when there is an increase in:

A)chorionic protein.
B)alpha fetoprotein.
C)amniotic protein.
D)embryonic protein.

Question 13

DNA formation and protein synthesis occur in the cell nucleus.

Question 14

A person with XXXY has the genetic disorder called __________ syndrome.

A)Turner
B)Klinefelter
C)Down
D)Fragile X

Question 15

In most cases of recessive disease, both parents of affected individuals are heterozygous carriers.

Question 16

What is the most common cause of Down syndrome?

A)Paternal nondisjunction
B)Maternal translocations
C)Maternal nondisjunction
D)Paternal translocation

Question 17

Frameshift mutation has no effect on amino acid sequence in protein synthesis.

Question 18

What is the role of DNA polymerase in DNA replication?

A)This enzyme travels along the single DNA strand adding the correct nucleotide to the new strand.
B)This enzyme travels along the double strand of DNA to unwind the nucleotides of the double helix.
C)This enzyme holds the double strand apart while the correct nucleotides are added to the strand.
D)This enzyme transports the double strand of DNA from the nucleus to the cytoplasm for protein formation.

Question 19

The term for an error in which homologous chromosomes fail to separate during meiosis or mitosis is:

A)aneuploidy.
B)nondisjunction.
C)polyploidy.
D)translocation.

Question 20

A child born with an autosomal dominant disease was most likely produced by the union of a normal parent with an affected heterozygous parent.

Question 21

A boy, 9 years of age, is admitted to the pediatric ward with hemophilia A.He inherited this condition through a ___________ trait.

A)sex-linked dominant
B)sex-influenced
C)sex-linked
D)sex-linked recessive

Question 22

If a boy has hemophilia A, he inherited it from:

A)his father.
B)his mother.
C)both parents.
D)his maternal grandparents.

Question 23

Match the genetic terms with the corresponding diseases. Terms may be used more than once.
Hemophilia

A)Autosomal dominant
B)Autosomal recessive
C)X-linked dominant
D)X-linked recessive

Question 24

A genetically normal male is always _____________ for genes on the X chromosome.

A)homozygous
B)heterozygous
C)hemizygous
D)ambizygous

Question 25

What is the second most commonly recognized genetic cause of mental retardation?

A)Down syndrome
B)Fragile X syndrome
C)Klinefelter syndrome
D)Turner syndrome

Question 26

Match the disease with its chromosomal abnormality.
A zygote has one chromosome with the normal complement of genes and one with a missing gene

A)Down syndrome
B)Klinefelter syndrome
C)Turner syndrome
D)Cri du chat

Question 27

Which is an important criterion for discerning autosomal recessive inheritance?

A)Consanguinity is often present.
B)Females are affected more than males.
C)The disease is seen in the parents and in the siblings.
D)On average, one half of the offspring of the carrier will be affected.

Question 28

Match the genetic terms with the corresponding diseases. Terms may be used more than once.
Cystic fibrosis

A)Autosomal dominant
B)Autosomal recessive
C)X-linked dominant
D)X-linked recessive

Question 29

Which of the following disorders has a mode of inheritance similar to hemophilia A?

A)Cri du chat syndrome
B)Duchenne muscular dystrophy (DMD)
C)Polycystic kidney disease
D)Down syndrome

Question 30

Consanguinity refers to the mating of:

A)two unrelated individuals.
B)persons when one has an autosomal dominant disorder.
C)persons having common family relations.
D)persons when one has a chromosomal abnormality.

Question 31

A couple has two children with a genetic disease.What is the probability that the next child will have the same genetic disease?

A)One sixth
B)One fourth
C)One third
D)One half

Question 32

Match the genetic terms with the corresponding diseases. Terms may be used more than once.
Sickle cell disease

A)Autosomal dominant
B)Autosomal recessive
C)X-linked dominant
D)X-linked recessive

Question 33

If a boy inherits a disease that is autosomal recessive, he inherited it from:

A)his father.
B)his mother.
C)both parents.
D)a grandparent.

Question 34

People who have neurofibromatosis have a varying degree of the condition because of the genetic principle of:

A)penetrance.
B)expressivity.
C)dominance.
D)recessiveness.

Question 35

Match the disease with its chromosomal abnormality.
An additional chromosome joining the normal homologous pair

A)Down syndrome
B)Klinefelter syndrome
C)Turner syndrome
D)Cri du chat

Question 36

Which genetic disease has been linked to a mutation of the tumor-suppressor gene?

A)Hemochromatosis
B)Retinoblastoma
C)Familial breast cancer
D)Hemophilia A

Question 37

Match the genetic terms with the corresponding diseases. Terms may be used more than once.
Huntington disease

A)Autosomal dominant
B)Autosomal recessive
C)X-linked dominant
D)X-linked recessive

Question 38

What is the blood type of a person who is heterozygous, having A and B alleles as codominant?

A)Type A
B)Type B
C)Type O
D)Type AB

Question 39

What is the chromosomal variation that causes Klinefelter syndrome?

A)Nondisjunction of the X chromosome in the father
B)Translocation of the X chromosome in the mother
C)Nondisjunction of X chromosome in the mother
D)Translocation of the Y chromosome in the father

Question 40

Cystic fibrosis is caused by an __________________ gene.

A)X-linked dominant
B)X-linked recessive
C)autosomal dominant
D)autosomal recessive

Question 41

Match the disease with its chromosomal abnormality.
Two X chromosomes and one Y chromosome

A)Down syndrome
B)Klinefelter syndrome
C)Turner syndrome
D)Cri du chat

Question 42

Match the disease with its chromosomal abnormality.
Single X chromosome with no homologous X or Y chromosome

A)Down syndrome
B)Klinefelter syndrome
C)Turner syndrome
D)Cri du chat