Deck 12: Units of Heredity: Chromosomes and Inheritance

Question 1

A trait such as albinism is seen with equal frequency in males and females. Two people who do not have the trait might have offspring who do have the trait, at a frequency of approximately one in four. What can you conclude about the inheritance of this trait?

A) recessive, X-linked
B) recessive, autosomal
C) recessive, caused by polyploidy
D) dominant, X-linked
E) dominant, autosomal

Answer 1

B

Question 2

What is a recessive disorder?

A) a genetic disorder with two functioning alleles
B) a genetic disorder that will express itself in the presence of one functioning allele
C) a genetic disorder that will express itself in the presence of two recessive alleles
D) a genetic disorder that involves change in chromosome number
E) a genetic disorder that involves change in chromosome structure

Answer 2

C

Question 3

A person with an inherited disorder has children with a person who does not have the condition. Half the children have the disorder, both sons and daughters. How is this condition inherited?

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

Answer 3

A

Question 4

Genes not found on the sex chromosomes will be found on:

A) X chromosomes.
B) Y chromosomes.
C) autosomes.
D) centrosomes.

Question 5

If a disease is caused by a dominant allele, it means that a person with the disease:

A) will always pass it on to all their children.
B) will pass it on to one-fourth of their children.
C) must be homozygous dominant for the allele.
D) must be heterozygous for the allele.
E) could be either homozygous or heterozygous for the allele.

Question 6

What is the connection between sickle-cell anemia and malaria?

A) Both are X-linked.
B) Both are autosomal recessive.
C) Both are dominant.
D) Heterozygotes for malaria have some resistance to sickle-cell anemia.
E) Heterozygotes for sickle-cell anemia have some resistance to malaria.

Question 7

Red-green color blindness is an X-linked recessive trait in humans. A color-blind woman and a man with normal vision have a son. What is the probability that the son is color blind?

A) 100 percent
B) 75 percent
C) 50 percent
D) 25 percent
E) 0 percent

Question 8

What do hemophilia, Duchenne muscular dystrophy, and red-green color blindness have in common?

A) They are X-linked.
B) They are more common in females than in males.
C) They are caused by inheritance of an extra sex chromosome.
D) They are caused by inheritance of an extra autosome.
E) The gene that causes them is on the Y chromosome.

Question 9

What percent of males have some degree of color blindness?

A) 0.5 percent
B) 5 percent
C) 0.8 percent
D) 8 percent
E) 10 percent

Question 10

A woman who is a carrier for the hemophilia gene has a child with a man who does not have hemophilia. Which prediction is correct?

A) All of the sons and none of the daughters will have hemophilia.
B) All of the daughters and none of the sons will have hemophilia.
C) Half of the sons and half of the daughters will have hemophilia.
D) Half of the sons and none of the daughters will have hemophilia.
E) Half of the daughters and none of the sons will have hemophilia.

Question 11

An autosomal recessive disorder:

A) requires that only one parent be a carrier.
B) displays its symptoms only in heterozygotes.
C) is more frequent in males than females.
D) will appear only in children of parents who both carry the gene.
E) is dominant in females.

Question 12

Regarding the human sex chromosomes, which statement is correct?

A) The Y chromosome carries a greater number of genes than does the X chromosome.
B) X and Y are different in size but carry nearly equal numbers of genes.
C) The X chromosome carries more genes than does the Y chromosome.
D) The X chromosome carries only gender-related genes.
E) The X chromosome carries the genes for the development of male phenotype.

Question 13

If a daughter expresses an X-linked recessive gene, she probably inherited the trait from:

A) her mother.
B) her father.
C) both parents.
D) neither parent.
E) her grandmother.

Question 14

Color blindness is caused by an X-linked recessive gene. A color-blind man and a woman with normal vision whose father was color blind have a son. The probability that their son is color blind is:

A) 0.25 (or 25 percent).
B) 0.50 (or 50 percent).
C) 0.75 (or 75 percent).
D) 1.00 (or 100 percent).
E) none of these.

Question 15

A person who has a recessive disorder but does not have the disorder him or herself is said to be a/an:

A) aneuploid.
B) aberration.
C) carrier.
D) hybrid.

Question 16

Why do X-linked conditions appear more frequently in males than in females?

A) A male with a nonfunctioning allele on the X chromosome does not have another allele of that gene on the Y chromosome that could cover up the nonfunctioning one.
B) Males have no X chromosomes.
C) The Y chromosome carries many alleles that are recessive to alleles on the X chromosome.
D) Males are more likely to inherit an extra chromosome than females.
E) Females have no X chromosomes.

Question 17

A woman who does not carry the color-blindness allele has children with a man who is color blind. What proportion of their children will be color blind?

A) all
B) 1/4
C) 1/2
D) 3/4
E) none

Question 18

A person who is heterozygous for the Huntington disease (HD) allele has offspring with someone who does not have HD. What proportion of their children will have HD?

A) 1/16
B) 1/10
C) 1/8
D) 1/4
E) 1/2

Question 19

Who is a "carrier" of X-linked disorders, such as hemophilia and color blindness?

A) a person who has the X-linked disorder
B) a heterozygous female who is normal but carries one nonfunctioning allele
C) a homozygous female who carries the normal alleles
D) a male who carries the nonfunctioning allele
E) a male who carries the functioning allele

Question 20

What condition is caused by a dominant allele of a single gene?

A) Down syndrome
B) sickle-cell anemia
C) Huntington disease
D) color blindness
E) Turner syndrome

Question 21

A person with the genotype XO is mainly female, phenotypically. A person with the genotype XXY is mainly male. What can you conclude about the Y chromosome?

A) It has the same genes as X, just different alleles.
B) It has the same genes as X, in different orientation.
C) A Y chromosome confers maleness, regardless of the number of X chromosomes.
D) The only genes it carries are for female development.
E) A human cannot survive without a Y chromosome.

Question 22

If more than one sperm fertilizes an egg, which of the following can result?

A) an autosomal dominant disorder
B) an autosomal recessive disorder
C) aneuploidy
D) polyploidy

Question 23

What is one difference between polyploidy and aneuploidy?

A) Polyploidy is extra sets of chromosomes; aneuploidy occurs when there are either more or fewer chromosomes than normally exist in its species full set.
B) Humans can be viable as polyploids but not as aneuploids.
C) Polyploidy is extra sex chromosomes; aneuploidy is extra autosomes.
D) Polyploidy is one extra chromosome; aneuploidy is one missing chromosome.
E) Polyploidy causes diseases and disorders in humans; aneuploidy does not.

Question 24

If a diploid cell from an organism has 46 chromosomes, how many chromosomes are likely to be found in a gamete that is the result of nondisjunction?

A) 46 or 92
B) 23 or 22
C) 21 or 22
D) 22 or 24
E) 24 or 25

Question 25

You are tracking the inheritance of a genetic disorder through a family's pedigree, and you notice that it shows up in every generation. The disorder is most likely:

A) recessive.
B) dominant.
C) X-linked recessive.

Question 26

Which condition or disease is caused by aneuploidy?

A) sickle-cell anemia
B) hemophilia
C) malaria
D) color blindness
E) Down syndrome

Question 27

The human genome has how many pairs of autosomal chromosomes?

A) 46 pairs
B) 44 pairs
C) 23 pairs
D) 22 pairs
E) 24 pairs

Question 28

Nondisjunction of the X chromosomes may occur during formation of gametes and produce two kinds of eggs. If normal sperm fertilizes these two kinds of eggs, which of the following pairs of genotypes are possible?

A) XX and XY
B) XXY and XO
C) XYY and XO
D) XYY and YO

Question 29

In humans, aneuploidy is fairly common yet goes largely unrecognized as a genetic problem. This is because:

A) it produces autosomal recessive individuals who don't always express the disorder.
B) its effects are usually hidden.
C) it actually produces healthy individuals.
D) it often results in miscarriage of embryos.

Question 30

In a pedigree chart, a darkened square demonstrates a:

A) diseased male.
B) diseased female.
C) normal male.
D) normal female.

Question 31

Which of the following is an autosomal recessive disorder?

A) hemophilia
B) Huntington disease
C) Down syndrome
D) sickle-cell anemia
E) Turner syndrome

Question 32

If a zygote has the genotype XYY, how many total chromosomes were in the sperm before it fused with the egg?

A) 20
B) 21
C) 22
D) 23
E) 24

Question 33

What is nondisjunction?

A) failure of sperm and egg to fuse in fertilization
B) failure of cells to divide by cytokinesis in meiosis
C) failure of chromosomes to duplicate before mitosis or meiosis
D) failure of homologous chromosomes or sister chromatids to separate in meiosis
E) an extra duplication of the chromosomes before mitosis or meiosis

Question 34

The state of having more than two sets of chromosomes is called:

A) autosomal.
B) dominant.
C) polyploidy.
D) aneuploidy.
E) nondisjunction.

Question 35

A woman is missing one of her X chromosomes. With which of the following conditions would she be diagnosed?

A) Turner syndrome
B) polyploidy
C) a chromosomal deletion
D) Klinefelter syndrome
E) cancer

Question 36

A study of several pedigrees demonstrates that two parents are normal. If some of their children express a trait, then the trait is controlled by a:

A) codominant gene.
B) simple dominant gene.
C) recessive gene.
D) sex-linked gene.

Question 37

Down syndrome in humans is caused by:

A) an extra X chromosome.
B) an extra y chromosome.
C) three copies of chromosome 21.
D) three copies of chromosome 13.
E) a single copy of chromosome 21.

Question 38

A pedigree is a representation of:

A) a genetic family tree.
B) a series of chromosomes arranged in order.
C) the inheritance pattern of recessive disorders.
D) the inheritance pattern of dominant disorders.
E) all the genetic disorders that can be inherited.

Question 39

Which of the following genetic disorders is caused by a dominant allele but does not produce symptoms until the affected individual is well into adulthood?

A) Turner syndrome
B) Down syndrome
C) Huntington disease
D) sickle-cell anemia
E) hemophilia

Question 40

Aneuploid human embryos are least likely to survive except those involving:

A) chromosome 1, 2, 3, X, Y.
B) chromosome 1, 2, 3, 4, 5.
C) chromosome 13, 18, 21, X, Y.
D) chromosome 6, 7, 8, 9, 10.
E) chromosome 11, 12, 14, 15.

Question 41

A carrier for a genetic disorder will pass the allele to all of their offspring.

Question 42

When a fragment breaks from a chromosome and rejoins it, in a flipped orientation, the result is called a/an:

A) deletion.
B) polyploidy.
C) inversion.
D) aneuploidy.
E) translocation.

Question 43

A chromosome that has been broken and has lost a section has had a/an:

A) aneuploidy.
B) inversion.
C) deletion.
D) duplication.
E) translocation.

Question 44

A person must have two alleles for hemoglobin S in order to suffer from sickle-cell anemia.

Question 45

What is a possible cause of the chromosomal aberration called a "duplication"?

A) unequal crossing over
B) exchange between non-homologous chromosomes
C) a chromosome fragment that breaks off and does not rejoin any chromosome
D) breaking of a chromosome fragment, then rejoining in a flipped orientation
E) nondisjunction

Question 46

Women do not express X-linked recessive characters.

Question 47

Polyploidy is better tolerated in plants than in animals.

Question 48

Cri-du-chat syndrome babies are mentally challenged and have an abnormal larynx that makes sounds like the cry of a cat. This disorder is due to a/an:

A) deletion in chromosome 5.
B) inversion in chromosome 2.
C) translocation between chromosome 9 and 22.
D) duplication in chromosome 7.
E) trisomy 21.

Question 49

A karyotype you are viewing shows an extra piece of chromosome 1 attached to chromosome 22. What type of abnormality caused this?

A) inversion
B) deletion
C) translocation
D) nondisjunction
E) sex-linked

Question 50

Match the following.

A) aneuploidy
B) nondisjunction
C) duplication
D) translocation
E) deletion
This produces cri-du-chat syndrome.

Question 51

Match the following.

A) aneuploidy
B) nondisjunction
C) duplication
D) translocation
E) deletion
This event may occur during meiosis I or meiosis II.

Question 52

A karyotype reveals that a woman is carrying a fetus that has 47 chromosomes. The test reveals that the genotype of the fetus is XXY. Which of the following statements is correct?

A) The fetus has Down syndrome, and most likely a nondisjunction event occurred in the mother during egg formation.
B) The fetus has Turner syndrome, and most likely a nondisjunction event occurred in the mother during egg formation.
C) The fetus has Klinefelter syndrome.
D) The fetus has an autosomal disorder.

Question 53

Which of the following combinations of chromosomes would be found in a person afflicted with Turner syndrome?

A) XXY
B) XYY
C) XX
D) XY
E) XO

Question 54

A single nondisjunction event results in some gametes with more chromosomes and some gametes with fewer chromosomes.

Question 55

What single attribute determines that a human fetus is male?

A) the absence of a second X chromosome
B) the absence of a Y chromosome
C) the presence of a Y chromosome
D) the presence of two X chromosomes

Question 56

Which of the following is a transfer of genes between non-homologous chromosomes?

A) duplication
B) crossing over
C) inversion
D) deletion
E) translocation

Question 57

If one of your parents has Huntington disease and is heterozygous for the disorder, you have a 50 percent chance of inheriting the disease.

Question 58

Match the following.

A) aneuploidy
B) nondisjunction
C) duplication
D) translocation
E) deletion
Only 1 percent of human embryos with this condition survive.

Question 59

Nondisjunction in somatic cells can result in aneuploid cells. This may give rise to:

A) Down syndrome.
B) Turner syndrome.
C) Klinefelter syndrome.
D) cancer.
E) cri-du-chat syndrome.

Question 60

Match the following.

A) aneuploidy
B) nondisjunction
C) duplication
D) translocation
E) deletion
Non-homologous chromosomes have exchanged parts.

Question 61

Explain why a female can be heterozygous for an X-linked gene but a male cannot.

Question 62

Duchenne muscular dystrophy is a recessive disorder resulting in a wasting away of the muscles. How would you design a study to determine if the disorder is X-linked or autosomal? How would you be able to determine if it is X-linked or autosomal?

Question 63

________ is the condition when an individual has three copies of chromosome 21.

Question 64

Refer to the figure below, and then answer the question that follows.
Nondisjunction in meiosis gives rise to gametes with abnormal chromosome numbers. Which event is likely to produce a higher percentage of abnormal gametes?

A) failure of homologous chromosomes to separate at meiosis I
B) failure of homologous chromosomes to separate at meiosis II
C) failure of sister chromatids to separate at meiosis I
D) failure of sister chromatids to separate at meiosis II
E) failure of sister chromatids to separate at mitosis

Question 65

Hemophelia is an X-linked recessive disorder. A mother without the allele and a father with the allele have a daughter. The daughter then marries a man with hemophilia. What is the genotype of the daughter? What is the probability that the daughter's children will develop the disease?

Question 66

The condition in which an organism has more than two sets of chromosomes is called ________, while having either more or fewer than the normal number of a particular chromosome is called ________.

Question 67

Match the following.

A) aneuploidy
B) nondisjunction
C) duplication
D) translocation
E) deletion
This has been involved in producing gene families and has been vital to evolution.

Question 68

Refer to the figure below, and then answer the question that follows.
The last members of the Russian Royal Family were executed during the Russian Revolution. Assume the revolution never took place and Alexis, son of Czar Nicholas II and Alexandra, survived and married into the British Royal Family. What is the probability that his children would have hemophilia? What is the probability his children would be carriers for hemophilia?

Question 69

Hemophilia, Duchenne muscular dystrophy, and color blindness are examples of ________ disorders.

Question 70

A person with only one allele for a recessive condition who does not have the condition is called a ________.

Question 71

Phenylketonuria is the most commonly inherited genetic disorder that affects nervous system development. It occurs in 1 out of every 10,000 births in the United States and Europe. How would you design a study to determine if phenylketonuria is an autosomal dominant or autosomal recessive disorder? How would you be able to determine if it is dominant or recessive?

Question 72

Explain what causes aneuploidy.

Question 73

You have studied the presence of a trait in the members of three generations of a family. With this information, you constructed a ________ to track how the trait was passed down through the generations.