Deck 19: Human Genetics

Question 1

Down syndrome is due to an extra

A)X chromosome.
B)Y chromosome.
C)autosome.
D)X chromosome or an extra Y chromosome.

Answer 1

C

Question 2

Most nondisjunction embryos fail to survive.

Answer 2

True

Question 3

Karyotyping of chromosomes may be done immediately from cells obtained by amniocentesis.
Cells need to be cultured to get enough for karyotyping,so it may take up to four weeks before the karyotype can be done.

Answer 3

False

Question 4

Monosomy could result from

A)an ovum of 24 chromosomes fertilized by a sperm with 23 chromosomes.
B)an ovum of 22 chromosomes fertilized by a sperm with 23 chromosomes.
C)an ovum of 23 chromosomes fertilized by a sperm with 23 chromosomes.
D)None apply.

Question 5

List the steps involved in the construction of a karyotype.

Question 6

Nondisjunction can only occur with autosomes,not the sex chromosomes.
Nondisjunction may occur with any type of chromosome.

Question 7

When does nondisjunction occur?

A)anaphase of mitosis
B)telophase of mitosis
C)anaphase of meiosis I or II
D)metaphase of meiosis II

Question 8

A display of an individual's chromosomes arranged by size,shape,and banding patterns is its

A)somatotype.
B)karyotype.
C)syndrome.
D)chromotype.

Question 9

Blood tests done with pregnant women routinely test for all of the following chemicals EXCEPT

A)Vitamin C.
B)human chorionic gonadotropin.
C)estriol.
D)alpha-fetoprotein.

Question 10

A human female body cell contains

A)46 chromosomes.
B)44 autosomes.
C)2 X chromosomes.
D)All apply.

Question 11

Which condition occurs as a result of nondisjunction?

A)Down syndrome
B)Turner syndrome
C)Poly-x syndrome
D)All apply.

Question 12

What procedure is used to obtain embryonic or fetal chromosomes for karyotyping?

A)chorionic villi sampling (CVS)
B)ultrasonography
C)amniocentesis
D)both chorionic villi sampling (CVS)or amniocentesis are used

Question 13

In adults,the cell used most often for karyotyping is a

A)red blood cell.
B)skin cell.
C)gamete.
D)white blood cell.

Question 14

Another name for Down syndrome is

A)trisomy 23.
B)monosomy 15.
C)trisomy 21.
D)monosomy 20.

Question 15

In preparing a cell sample for karyotyping,when are the cells most visible?

A)prophase
B)metaphase
C)anaphase
D)telophase

Question 16

When can chorionic villi sampling be done?

A)2 weeks of pregnancy
B)5 weeks of pregnancy
C)8 weeks of pregnancy
D)10 weeks of pregnancy

Question 17

A mature red blood cell is useful for karyotyping.
A white blood cell is useful for karyotyping.A mature red blood cell has no nucleus,so it is useless for karyotyping.

Question 18

Autosomes are

A)human chromosomes.
B)sex chromosomes.
C)nonsex "self" chromosomes.
D)abnormal chromosomes.

Question 19

The sex of a child is determined by the

A)sperm.
B)egg.
C)either sperm or egg.

Question 20

Trisomy could result from

A)an ovum of 24 chromosomes fertilized by a sperm with 23 chromosomes.
B)an ovum of 22 chromosomes fertilized by a sperm with 23 chromosomes.
C)an ovum of 23 chromosomes fertilized by a sperm with 23 chromosomes.
D)None apply.

Question 21

Carriers for recessive disorders are

A)homozygous dominant.
B)heterozygous.
C)homozygous recessive.
D)either heterozygous or homozygous recessive.

Question 22

An individual that has a dominant allele will have the phenotype of the

A)dominant trait.
B)recessive trait.
C)neither trait.
D)both traits.

Question 23

A sex-linked gene inherited by a male comes from the

A)father.
B)mother.
C)father or the mother.
D)father and the mother.

Question 24

Which sex chromosome(s)is(are)needed for life?

A)X
B)Y
C)X and Y

Question 25

Poly-X females are

A)never fertile.
B)hermaphrodites.
C)normally fertile.
D)nonexistent.

Question 26

An individual with one Y and two or more X chromosomes has

A)Klinefelter syndrome.
B)Jacobs syndrome.
C)Turner syndrome.
D)poly-X syndrome.

Question 27

Genotype is

A)the genes of an individual.
B)the physical appearance of an individual.
C)the alleles an individual has.
D)Both the genes of an individual and the alleles an individual has are correct.

Question 28

Can a female have an X-linked disorder?

A)never
B)yes,frequently occurs
C)yes,infrequently occurs
D)yes,always occurs

Question 29

XYY individuals are usually

A)super males.
B)sterile females.
C)males with speech and reading problems.
D)nonexistent.

Question 30

An individual with XYY has

A)Klinefelter syndrome.
B)Jacobs syndrome.
C)Turner syndrome.
D)poly-X syndrome.

Question 31

A genotype of tt is

A)homozygous recessive.
B)homozygous dominant.
C)heterozygous.
D)sex-linkeD.

Question 32

Phenotype is

A)the genes of an individual.
B)the physical appearance of an individual.
C)the alleles an individual has.
D)Both the physical appearance of an individual and the alleles an individual has are correct.

Question 33

An XO individual will have

A)Klinefelter syndrome.
B)Jacobs syndrome.
C)Turner syndrome.
D)poly-X syndrome.

Question 34

Which genotype is homozygous?

A)DD
B)dd
C)Dd
D)Both DD and dd are correct.

Question 35

YO individuals are

A)feminized males.
B)masculine females.
C)nonexistent.
D)normal males.

Question 36

A genotype of DD is

A)heterozygous.
B)homozygous recessive.
C)heterozygous recessive.
D)homozygous dominant.

Question 37

A genotype of Bb is

A)heterozygous.
B)homozygous recessive.
C)heterozygous recessive.
D)homozygous dominant.

Question 38

Turner syndrome is due to a(an)

A)extra sex chromosome.
B)missing sex chromosome.
C)extra autosome.
D)missing autosome.

Question 39

An individual with Klinefelter syndrome would be a

A)nonfunctional female.
B)functional female.
C)nonfunctional male.
D)functional male.

Question 40

An individual with Turner syndrome would be a

A)nonfunctional female.
B)functional female.
C)nonfunctional male.
D)functional male.

Question 41

The insertion of genetic material into human cells for treatment of a disorder is

A)a pedigree.
B)a genome.
C)amniocentesis.
D)gene therapy.

Question 42

What is the most lethal genetic disorder among Caucasians in the United States?

A)Down syndrome
B)Tay-Sach's disease
C)Spina bifida
D)Cystic fibrosis

Question 43

Which of the following is NOT a sex-linked inherited disorder?

A)Thalassemia
B)Color blindness
C)Hemophilia
D)Muscular dystrophy

Question 44

Color blindness is considered a sex-linked recessive disorder.Explain what this means.

Question 45

The most common virus class used as a vector is the

A)retrovirus.
B)herpes virus.
C)adenovirus.
D)liposome.

Question 46

If one parent has only dominant genes and the other has only recessive genes for a particular dominant genetic disorder,how many of their children should be affected by the disorder?

Question 47

The most common vector that is used to transport DNA into a cell for gene therapy is a(an)

A)virus.
B)bacteria.
C)cancer cell.
D)allergen.

Question 48

Which of the following are alternate ways to introduce DNA into a cell (other than viruses)?

A)direct insertion of DNA
B)attachment to a liposome
C)attachment to the cell membrane
D)All apply.

Question 49

If one parent has only dominant genes and the other has only recessive genes for a particular recessive genetic disorder,how many of their children should be affected by the disorder?

Question 50

What short-cut is used to predict the probability of inheriting a particular trait?

A)karyotype
B)electrophoresis
C)Punnett square
D)amniocentesis

Question 51

A genetic disorder can lead to the synthesis of an abnormal protein.

Question 52

Which of the following is NOT a dominant inherited disorder?

A)Neurofibromatosis
B)Achondroplasia
C)Hemophilia
D)Huntington disease

Question 53

An abnormal allele,leading to an abnormal channel protein,is the cause of

A)hemophiliA.
B)cystic fibrosis.
C)unattached earlobes.
D)asthma.

Question 54

One way for a genetic counselor to deduce inheritance patterns is to construct a diagram of the trait which is called a(an)

A)karyotype.
B)pedigree.
C)amniocentesis.
D)preimplantation genetic diagnosis.

Question 55

Which of the following is NOT a multiple gene inherited disorder?

A)Cleft-lip
B)Spina bifida
C)Tay-Sach's disease
D)Hydrocephalus

Question 56

Which of the following is NOT a recessive inherited disorder?

A)Cystic fibrosis
B)Phenylketonuria
C)Sickle-cell disease
D)Muscular dystrophy

Question 57

In which situation can a child born with a genetic disease have two normal parents?

A)when the disease gene is dominant and the parents are heterozygous
B)when the disease gene is recessive and the parents are heterozygous
C)when the disease gene is either dominant or recessive
D)it is not possible

Question 58

Over 50% of the genome codes for proteins.
Less than 2% of the genome codes for proteins.

Question 59

The order of 99.9% of the base pairs of all people is exactly the same.

Question 60

All the genetic information in all the chromosomes of an individual is their

A)genome.
B)karyotype.
C)pedigree.
D)All apply.