Question 1

Two parents are phenotypically normal, but one of their four biological children has a typical autosomal recessive trait. The other three children are phenotypically normal. It is very likely that:

Accepted Answer

A)   the affected child is a girl.
B)   the affected child is a boy.
C)   the trait was expressed by one of the grandparents of the children.
D)   the parents are both heterozygous for the trait.
E)   if the affected child eventually marries a phenotypically normal spouse, all of their children will have the trait.F) B) and D)
G) A) and E)

Question 2

Explain the principle behind using concordance values for monozygotic (MZ) and dizygotic (DZ) twins to determine the influence of genetic factors on individual differences for a trait.

Accepted Answer

Concordance values for monozygotic (MZ) ...

Question 3

The pedigree below shows the segregation of an autosomal recessive trait. What is the probability that the child of III-1 and III-2 will be affected? Assume that individuals from outside the families are homozygous normal.

Accepted Answer

A)   1/9
B)   1/64
C)   1/36
D)   1/12
E)   1/16F) A) and E)
G) C) and E)

Question 4

If the characteristic followed in the pedigree is X-linked recessive allele, what is III-1's genotype?

Accepted Answer

A)   hemizygous for a dominant allele
B)   hemizygous for a recessive allele
C)   definitely heterozygous
D)   definitely homozygous dominant
E)   either heterozygous or homozygous dominantF) B) and D)
G) B) and E)

Question 5

Fetal cell sorting is a(n) :

Accepted Answer

A)   method of obtaining fetal cells through amniocentesis.
B)   method of obtaining fetal cells through chorionic villus sampling.
C)   procedure for detecting and separating fetal cells from maternal blood cells.
D)   invasive procedure that allows a physician to directly take blood from the fetus to analyze for genetic conditions.
E)   method where a fetus who has a genetic condition can be treated before birth by providing it with healthy fetal cells.F) None of the above
G) A) and D)

Question 6

The ability to roll the tongue is caused by a dominant allele. A woman is a "roller," but one of her parents is not. What is the woman's genotype?

Accepted Answer

A)   homozygous dominant
B)   heterozygous
C)   homozygous recessive
D)   either homozygous recessive or homozygous dominant
E)   It cannot be determined from this information.F) All of the above
G) A) and E)

Question 7

Tony, who is not diseased, has a sister with cystic fibrosis (CF). Neither of his parents has CF. Tony is expecting a child with Tina. Tina's family history is unknown. If the frequency of heterozygotes in the general population is 1/50, what is the probability that Tony and Tina's child will have CF? Explain each factor in your calculation.

Accepted Answer

To calculate the probability that Tony a...

Question 8

What is the MOST likely mode of inheritance in the pedigree below?

Accepted Answer

A)   autosomal recessive
B)   autosomal dominant
C)   X-linked recessive
D)   X-linked dominant
E)   Y-linkedF) D) and E)
G) A) and B)

Question 9

Preimplantation genetic testing involves:

Accepted Answer

A)   testing a newborn infant for a genetic disorder immediately after birth.
B)   testing a single cell of an early embryo for a genetic disorder before the embryo is considered for implantation into the mother's uterus.
C)   testing multiple sperm from a man who is heterozygous for a serious genetic disorder and then using only sperm that have normal alleles for in vitro fertilizations.
D)   removing cells from a fetus, testing them for a genetic disorder, and then allowing abnormal fetuses to be aborted.
E)   testing primary oocytes (eggs)  for genetic disorders before using them for in vitro fertilizations.F) B) and E)
G) A) and D)

Question 10

The ability to roll the tongue is caused by a dominant allele. A woman is a "roller," but one of her parents is not. The woman is expecting a child with a man who is a "nonroller." What is the probability that their first child will be a "roller"?

Accepted Answer

A)   1/4
B)   0
C)   3/4
D)   1/2
E)   1F) A) and E)
G) C) and D)

Question 11

Most pedigrees showing the hypothetical human trait show the following characteristics:
 • Only males are affected.
• Affected fathers always pass the trait to sons.
What is the MOST likely mode of inheritance for this disorder?

Accepted Answer

A)   autosomal recessive
B)   autosomal dominant
C)   X-linked recessive
D)   X-linked dominant
E)   Y-linkedF) B) and D)
G) A) and B)

Question 12

If the phenotype followed in Pedigree 3 is autosomal recessive, then what is the genotype of I-1? Assume no new mutations and complete penetrance.

Accepted Answer

A)   homozygous dominant
B)   heterozygous
C)   homozygous recessive
D)   hemizygous dominant
E)   hemizygous recessiveF) All of the above
G) A) and D)

Question 13

What is/are the possible inheritance pattern(s)  for the characteristic in Pedigree 2? Assume no new mutations and complete penetrance.

Accepted Answer

A)   autosomal recessive only
B)   autosomal dominant only
C)   X-linked recessive only
D)   X-linked dominant only
E)   All of these are possible.F) All of the above
G) A) and C)

Question 14

If the characteristic followed in the pedigree is autosomal recessive, what is III-1's genotype?

Accepted Answer

A)   either homozygous dominant or heterozygous
B)   definitely heterozygous
C)   definitely homozygous dominant
D)   must be homozygous recessive
E)   homozygous dominant since he is a male but a female would be heterozygousF) A) and E)
G) None of the above

Question 15

Tony, who is not diseased, has a sister with cystic fibrosis (CF). Neither of his parents has CF. Tony is expecting a child with Tina. Tina's family history is unknown. What is the probability that Tony is heterozygous for the CF gene? Explain your answer.

Accepted Answer

To determine the probability that Tony i...

Question 16

To establish a successful and cost-effective screening program for detecting adult heterozygous carriers of an autosomal recessive disease, which of the following is NOT important?

Accepted Answer

A)   Detection of the disorder is possible in the fetus.
B)   The disease is clinically significant.
C)   A high-risk population can be identified.
D)   Genetic counseling is provided with the testing.
E)   An effective treatment is available for the disorder.F) B) and E)
G) D) and E)

Question 17

Draw a four-generation pedigree, following color blindness, using the following information: In generation I, neither parent is color blind. In generation II, a son (II-1) is color blind, a daughter (II-2) is not. II-2 and a man with normal color vision (II-3) have a daughter (III-1) who is not color blind. III-1 and a man with normal color vision (III-2) have a daughter (IV-1) who is not color blind. Write in all the genotypes that are known. Use symbols Xc and Y to follow the sex chromosomes and sex-linked genes.

Accepted Answer

Here is the four-generation pedigree for...

Question 18

Most pedigrees showing the hypothetical human trait show the following characteristics: 
• If a phenotypically normal woman with an affected father has children with an unaffected man, half of the sons and none of the daughters are affected.
• Affected females always have an affected father and an affected maternal grandfather.
• The trait is never passed from father to son.
What is the MOST likely mode of inheritance for this disorder?

Accepted Answer

A)   autosomal recessive
B)   autosomal dominant
C)   X-linked recessive
D)   X-linked dominant
E)   Y-linkedF) B) and E)
G) B) and C)

Question 19

Heterozygous genetic screening is used mainly to:

Accepted Answer

A)   detect genetic disorders in newborn infants.
B)   detect adult members of a particular population who may be heterozygous carriers for recessive disorders.
C)   detect in healthy adults the presence of a mutant allele that may predispose them to some serious health problem later in life.
D)   detect fetuses who may be heterozygous carriers for recessive disorders and may eventually be at risk of having children of their own with these disorders.
E)   detect adults that may be heterozygous for serious autosomal dominant disorders.F) A) and B)
G) C) and D)

Question 20

Which description of a Y-linked trait in humans is CORRECT?

Accepted Answer

A)   All the sons of an affected father will be affected with the trait.
B)   Half the sons of a mother whose father was affected with the trait will be affected.
C)   Half the sons of an affected father will not be affected with the trait and the other half will be infertile.
D)   All the daughters of an affected father will be phenotypically normal but half of their own sons will be affected with the trait.
E)   The parents of an affected man likely were both phenotypically normal.F) A) and B)
G) B) and C)

Exam 6: Pedigree Analysis, Applications, and Genetic Testing

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Here is the four-generation pedigree for...
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If the phenotype followed in Pedigree 3 is autosomal recessive, then what is the genotype of I-1? Assume no new mutations and complete penetrance.

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Preimplantation genetic testing involves:

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Which description of a Y-linked trait in humans is CORRECT?

Correct Answer
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What is the MOST likely mode of inheritance in the pedigree below?

Correct Answer
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To establish a successful and cost-effective screening program for detecting adult heterozygous carriers of an autosomal recessive disease, which of the following is NOT important?

Correct Answer
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Explain the principle behind using concordance values for monozygotic (MZ) and dizygotic (DZ) twins to determine the influence of genetic factors on individual differences for a trait.

Correct Answer
Answered by ExamLex AI
Concordance values for monozygotic (MZ) ...
View Answer

The ability to roll the tongue is caused by a dominant allele. A woman is a "roller," but one of her parents is not. What is the woman's genotype?

Correct Answer
verified

Tony, who is not diseased, has a sister with cystic fibrosis (CF). Neither of his parents has CF. Tony is expecting a child with Tina. Tina's family history is unknown. What is the probability that Tony is heterozygous for the CF gene? Explain your answer.

Correct Answer
Answered by ExamLex AI
To determine the probability that Tony i...
View Answer

Most pedigrees showing the hypothetical human trait show the following characteristics: • Only males are affected. • Affected fathers always pass the trait to sons. What is the MOST likely mode of inheritance for this disorder?

Correct Answer
verified

The ability to roll the tongue is caused by a dominant allele. A woman is a "roller," but one of her parents is not. The woman is expecting a child with a man who is a "nonroller." What is the probability that their first child will be a "roller"?

Correct Answer
verified

Two parents are phenotypically normal, but one of their four biological children has a typical autosomal recessive trait. The other three children are phenotypically normal. It is very likely that:

Correct Answer
verified

The pedigree below shows the segregation of an autosomal recessive trait. What is the probability that the child of III-1 and III-2 will be affected? Assume that individuals from outside the families are homozygous normal.

Correct Answer
verified

If the characteristic followed in the pedigree is autosomal recessive, what is III-1's genotype?

Correct Answer
verified

If the characteristic followed in the pedigree is X-linked recessive allele, what is III-1's genotype?

Correct Answer
verified

Correct Answer
Answered by ExamLex AI
To calculate the probability that Tony a...
View Answer

Correct Answer
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What is/are the possible inheritance pattern(s) for the characteristic in Pedigree 2? Assume no new mutations and complete penetrance.

Correct Answer
verified

Fetal cell sorting is a(n) :

Correct Answer
verified

Heterozygous genetic screening is used mainly to:

Correct Answer
verified

Exam 6: Pedigree Analysis, Applications, and Genetic Testing

Correct AnswerAnswered by ExamLex AIHere is the four-generation pedigree for...View AnswerShow Answer

If the phenotype followed in Pedigree 3 is autosomal recessive, then what is the genotype of I-1? Assume no new mutations and complete penetrance.

Correct AnswerverifiedShow Answer

Preimplantation genetic testing involves:

Correct AnswerverifiedShow Answer

Which description of a Y-linked trait in humans is CORRECT?

Correct AnswerverifiedShow Answer

What is the MOST likely mode of inheritance in the pedigree below?

Correct AnswerverifiedShow Answer

To establish a successful and cost-effective screening program for detecting adult heterozygous carriers of an autosomal recessive disease, which of the following is NOT important?

Correct AnswerverifiedShow Answer

Explain the principle behind using concordance values for monozygotic (MZ) and dizygotic (DZ) twins to determine the influence of genetic factors on individual differences for a trait.

Correct AnswerAnswered by ExamLex AIConcordance values for monozygotic (MZ) ...View AnswerShow Answer

The ability to roll the tongue is caused by a dominant allele. A woman is a "roller," but one of her parents is not. What is the woman's genotype?

Correct AnswerverifiedShow Answer

Tony, who is not diseased, has a sister with cystic fibrosis (CF). Neither of his parents has CF. Tony is expecting a child with Tina. Tina's family history is unknown. What is the probability that Tony is heterozygous for the CF gene? Explain your answer.

Correct AnswerAnswered by ExamLex AITo determine the probability that Tony i...View AnswerShow Answer

Most pedigrees showing the hypothetical human trait show the following characteristics: • Only males are affected. • Affected fathers always pass the trait to sons. What is the MOST likely mode of inheritance for this disorder?

Correct AnswerverifiedShow Answer

The ability to roll the tongue is caused by a dominant allele. A woman is a "roller," but one of her parents is not. The woman is expecting a child with a man who is a "nonroller." What is the probability that their first child will be a "roller"?

Correct AnswerverifiedShow Answer

Two parents are phenotypically normal, but one of their four biological children has a typical autosomal recessive trait. The other three children are phenotypically normal. It is very likely that:

Correct AnswerverifiedShow Answer

The pedigree below shows the segregation of an autosomal recessive trait. What is the probability that the child of III-1 and III-2 will be affected? Assume that individuals from outside the families are homozygous normal.

Correct AnswerverifiedShow Answer

If the characteristic followed in the pedigree is autosomal recessive, what is III-1's genotype?

Correct AnswerverifiedShow Answer

If the characteristic followed in the pedigree is X-linked recessive allele, what is III-1's genotype?

Correct AnswerverifiedShow Answer

Correct AnswerAnswered by ExamLex AITo calculate the probability that Tony a...View AnswerShow Answer

Correct AnswerverifiedShow Answer

What is/are the possible inheritance pattern(s) for the characteristic in Pedigree 2? Assume no new mutations and complete penetrance.

Correct AnswerverifiedShow Answer

Fetal cell sorting is a(n) :

Correct AnswerverifiedShow Answer

Heterozygous genetic screening is used mainly to:

Correct AnswerverifiedShow Answer

Correct Answer
Answered by ExamLex AI
Here is the four-generation pedigree for...
View Answer

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
Answered by ExamLex AI
Concordance values for monozygotic (MZ) ...
View Answer

Correct Answer
verified

Correct Answer
Answered by ExamLex AI
To determine the probability that Tony i...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
Answered by ExamLex AI
To calculate the probability that Tony a...
View Answer

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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