Question 1

In pea plants,the allele for tall (T)is dominant to the allele for short (t).The genotype for a short pea plant is __.

Accepted Answer

A)  TT 
B)  Tt 
C)  tt 
D)  Tt or tt 
E)  TT or tt 
A)  TT 
B)  Tt 
C)  tt 
D)  Tt or tt 
E)  TT or tt

Question 2

In the Foofnagle family,the trait of being able to yodel affects members of both sexes in every generation.This trait could be

Accepted Answer

A)  autosomal recessive or autosomal dominant. 
B)  autosomal recessive but not autosomal dominant. 
C)  autosomal dominant but not autosomal recessive. 
D)  conclusive or inconclusive. 
E)  caused by something in the environment and not inherited at all. 
A)  autosomal recessive or autosomal dominant. 
B)  autosomal recessive but not autosomal dominant. 
C)  autosomal dominant but not autosomal recessive. 
D)  conclusive or inconclusive. 
E)  caused by something in the environment and not inherited at all.

Question 3

A very narrow pedigree,such as that for Egypt's Ptolemy dynasty,reflects

Accepted Answer

A)  families with many children. 
B)  families with many adopted children. 
C)  a very mild phenotype. 
D)  many uncles marrying their nephews. 
E)  families with many relatives having children with blood relatives. 
A)  families with many children. 
B)  families with many adopted children. 
C)  a very mild phenotype. 
D)  many uncles marrying their nephews. 
E)  families with many relatives having children with blood relatives.

Question 4

An autosomal dominant trait

Accepted Answer

A)  passes from mother to son only. 
B)  skips generations. 
C)  can be carried by unaffected individuals. 
D)  can affect either sex. 
E)  is only seen when homozygous. 
A)  passes from mother to son only. 
B)  skips generations. 
C)  can be carried by unaffected individuals. 
D)  can affect either sex. 
E)  is only seen when homozygous.

Question 5

The genotypic ratio expected from a dihybrid cross involving complete dominance is

Accepted Answer

A)  3:1. 
B)  1:2:1. 
C)  9:3:1. 
D)  9:3:3:1. 
E)  4:1. 
A)  3:1. 
B)  1:2:1. 
C)  9:3:1. 
D)  9:3:3:1. 
E)  4:1.

Question 6

The difference in mode of inheritance between Huntington disease and cystic fibrosis is that

Accepted Answer

A)  Huntington disease only affects men and cystic fibrosis affects both sexes. 
B)  Huntington disease skips generations and only affects children, whereas cystic fibrosis can strike at any age and never skips generations. 
C)  Huntington disease does not skip generations but cystic fibrosis can. 
D)  A person with Huntington disease can have unaffected parents, but a person with cystic fibrosis must have an affected parent. 
E)  Huntington disease affects females and cystic fibrosis affects males. 
A)  Huntington disease only affects men and cystic fibrosis affects both sexes. 
B)  Huntington disease skips generations and only affects children, whereas cystic fibrosis can strike at any age and never skips generations. 
C)  Huntington disease does not skip generations but cystic fibrosis can. 
D)  A person with Huntington disease can have unaffected parents, but a person with cystic fibrosis must have an affected parent. 
E)  Huntington disease affects females and cystic fibrosis affects males.

Question 7

Ian and Bryony are both carriers for two autosomal recessive disorders,PKU (chromosome 12)and cystic fibrosis (chromosome 7).They are expecting a daughter.What is the probability that she will have PKU but not CF?

Accepted Answer

A)  3/4. 
B)  9/16. 
C)  3/16. 
D)  1/2. 
E)  1/16. 
A)  3/4. 
B)  9/16. 
C)  3/16. 
D)  1/2. 
E)  1/16.

Question 8

Which of the following represents a monohybrid cross?

Accepted Answer

A)  Bb x Bb 
B)  AaBb x AaBb 
C)  BB x bb 
D)  AABB x aabb 
E)  a x b 
A)  Bb x Bb 
B)  AaBb x AaBb 
C)  BB x bb 
D)  AABB x aabb 
E)  a x b

Question 9

Mendel called physical units responsible for the inheritance of traits "characters." The basis for his first law is that characters

Accepted Answer

A)  separate from each other during meiosis. 
B)  are carried on separate chromosomes. 
C)  can exist as multiple alleles. 
D)  are inherited in random combinations. 
E)  can be cloned using nuclear transfer. 
A)  separate from each other during meiosis. 
B)  are carried on separate chromosomes. 
C)  can exist as multiple alleles. 
D)  are inherited in random combinations. 
E)  can be cloned using nuclear transfer.

Question 10

Jaden is six years old.His sister Hillary has the autosomal recessive condition neuronal ceroid lipofuscinosis that affects learning and coordination.Their parents are healthy.The probability that Jaden is a homozygote for the wild type allele of the gene that causes the condition is

Accepted Answer

A)  1/8. 
B)  1/4. 
C)  1/3. 
D)  2/3. 
E)  0. 
A)  1/8. 
B)  1/4. 
C)  1/3. 
D)  2/3. 
E)  0.

Question 11

In a human pedigree that traces the inheritance of sickle cell disease,a half-filled circle represents a

Accepted Answer

A)  male with the disease. 
B)  female with the disease. 
C)  heterozygous male. 
D)  heterozygous female. 
E)  individual who died. 
A)  male with the disease. 
B)  female with the disease. 
C)  heterozygous male. 
D)  heterozygous female. 
E)  individual who died.

Question 12

A Punnett square displays

Accepted Answer

A)  members of a family and their phenotypes. 
B)  paired chromosomes in size order. 
C)  DNA sequences and the proteins they encode. 
D)  the probabilities of how alleles combine in offspring. 
E)  only the males in a pedigree. 
A)  members of a family and their phenotypes. 
B)  paired chromosomes in size order. 
C)  DNA sequences and the proteins they encode. 
D)  the probabilities of how alleles combine in offspring. 
E)  only the males in a pedigree.

Question 13

The second generation resulting from a genetic cross is the _______ generation.

Accepted Answer

A)  P1 
B)  P2 
C)  F1 
D)  F2 
E)  L1 
A)  P1 
B)  P2 
C)  F1 
D)  F2 
E)  L1

Question 14

In a human pedigree that traces the inheritance of albinism,a filled square represents a

Accepted Answer

A)  male with albinism. 
B)  female with albinism. 
C)  heterozygous male. 
D)  heterozygous female. 
E)  a female who is homozygous for the wild type allele. 
A)  male with albinism. 
B)  female with albinism. 
C)  heterozygous male. 
D)  heterozygous female. 
E)  a female who is homozygous for the wild type allele.

Question 15

A very difficult aspect of Huntington disease is that

Accepted Answer

A)  it affects different people in a family at very different ages. 
B)  it affects different people in a family in different parts of the body. 
C)  it affects different people in a family in different parts of the brain. 
D)  a family may include individuals at different stages of the illness. 
E)  the disease can become infectious, and pass even to those who do not have the mutation. 
A)  it affects different people in a family at very different ages. 
B)  it affects different people in a family in different parts of the body. 
C)  it affects different people in a family in different parts of the brain. 
D)  a family may include individuals at different stages of the illness. 
E)  the disease can become infectious, and pass even to those who do not have the mutation.

Question 16

When Mendel crossed pure breeding peas having yellow seed color (YY)with pure breeding peas having green seed color (yy),all of the offspring had yellow seed color.These results mean that yellow seed color is the

Accepted Answer

A)  genotype. 
B)  dominant phenotype. 
C)  mode of inheritance. 
D)  recessive phenotype. 
E)  mutant phenotype. 
A)  genotype. 
B)  dominant phenotype. 
C)  mode of inheritance. 
D)  recessive phenotype. 
E)  mutant phenotype.

Question 17

Eric and Janelle are carriers of the recessive allele causing Tay-Sachs disease,which is lethal in early childhood.If they have a healthy child,what is the probability that this child would NOT be a carrier of Tay-Sachs disease?

Accepted Answer

A)  1 
B)  2/3 
C)  1/2 
D)  1/3 
E)  78 
A)  1 
B)  2/3 
C)  1/2 
D)  1/3 
E)  78

Question 18

Sickle cell disease is inherited as an autosomal recessive trait.The genotype of an individual with sickle cell disease is

Accepted Answer

A)  homozygous dominant. 
B)  homozygous recessive. 
C)  heterozygous dominant. 
D)  heterozygous recessive. 
E)  unable to be determined by the phenotype. 
A)  homozygous dominant. 
B)  homozygous recessive. 
C)  heterozygous dominant. 
D)  heterozygous recessive. 
E)  unable to be determined by the phenotype.

Question 19

A heterozygote has

Accepted Answer

A)  two different alleles for a gene. 
B)  two of the same alleles for a gene. 
C)  only one allele for a gene. 
D)  an extra genome. 
E)  one copy of each sex chromosome. 
A)  two different alleles for a gene. 
B)  two of the same alleles for a gene. 
C)  only one allele for a gene. 
D)  an extra genome. 
E)  one copy of each sex chromosome.

Question 20

A(n)______ cross yields a genotypic ratio of 1:2:1 and a phenotypic ratio of 3:1.

Accepted Answer

A)  allelic 
B)  monohybrid 
C)  test 
D)  dihybrid 
E)  trihybrid 
A)  allelic 
B)  monohybrid 
C)  test 
D)  dihybrid 
E)  trihybrid

Exam 4: Single-Gene Inheritance

In pea plants,the allele for tall (T)is dominant to the allele for short (t).The genotype for a short pea plant is __.

In the Foofnagle family,the trait of being able to yodel affects members of both sexes in every generation.This trait could be

A very narrow pedigree,such as that for Egypt's Ptolemy dynasty,reflects

An autosomal dominant trait

The genotypic ratio expected from a dihybrid cross involving complete dominance is

The difference in mode of inheritance between Huntington disease and cystic fibrosis is that

Ian and Bryony are both carriers for two autosomal recessive disorders,PKU (chromosome 12)and cystic fibrosis (chromosome 7).They are expecting a daughter.What is the probability that she will have PKU but not CF?

Which of the following represents a monohybrid cross?

Mendel called physical units responsible for the inheritance of traits "characters." The basis for his first law is that characters

Jaden is six years old.His sister Hillary has the autosomal recessive condition neuronal ceroid lipofuscinosis that affects learning and coordination.Their parents are healthy.The probability that Jaden is a homozygote for the wild type allele of the gene that causes the condition is

In a human pedigree that traces the inheritance of sickle cell disease,a half-filled circle represents a

A Punnett square displays

The second generation resulting from a genetic cross is the _______ generation.

In a human pedigree that traces the inheritance of albinism,a filled square represents a

A very difficult aspect of Huntington disease is that

When Mendel crossed pure breeding peas having yellow seed color (YY)with pure breeding peas having green seed color (yy),all of the offspring had yellow seed color.These results mean that yellow seed color is the

Eric and Janelle are carriers of the recessive allele causing Tay-Sachs disease,which is lethal in early childhood.If they have a healthy child,what is the probability that this child would NOT be a carrier of Tay-Sachs disease?

Sickle cell disease is inherited as an autosomal recessive trait.The genotype of an individual with sickle cell disease is

A heterozygote has

A(n)______ cross yields a genotypic ratio of 1:2:1 and a phenotypic ratio of 3:1.

Overview of Genetics

Cells

Meiosis and Development

Beyond Mendels Law

Matters of Sex

Multifactorial Traits

Genetics of Behavior

DNA Structure and Replication

Gene Action: From Dna to Protein

Gene Expression and Epigenetics

Gene Mutation

Chromosomes

Constant Allele Frequencies

Changing Allele Frequencies

Human Ancestry

Genetics of Immunity

Genetics of Cancer

Genetic Technologies: Amplifying, Modifying, and Monitoring DNA

Genetic Testing and Treatment

Reproductive Technologies

Genomics

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