Deck 10: Patterns of Inheritance

Question 1

If a healthy young couple are both carriers of cystic fibrosis,the chance that their future child will have this serious illness is

A) 0%.
B) 25%.
C) 75%.
D) 50%.
E) 100%.

Answer 1

B
Explanation: The probability of inheritance of a single gene trait can be calculated using Mendelian principles. A four square Punnett square can be produced to obtain the answer. 

Question 2

Genotype means the

A) number of gametes in an individual.
B) combination of alleles in an individual.
C) number of chromosomes in an individual.
D) observable expression of the genes in an individual.
E) genes an individual has.

Answer 2

B
Explanation: The genotype of an individual is the set of alleles found for any given gene.

Question 3

Mendel called a trait that is masked

A) homozygous.
B) heterozygous.
C) dominant.
D) recessive.
E) No answer is correct.

Answer 3

D
Explanation: A recessive allele has effects which are masked or covered by the effects of a dominant allele.

Question 4

Phenotype means the

A) number of gametes in an individual.
B) number of chromosomes in an individual.
C) combination of alleles in an individual.
D) genes an individual has.
E) observable expression of the genes in an individual.

Question 5

The pea plant (Pisum sativum)is a good choice for studying heredity because it

A) develops slowly.
B) produces only a few offspring.
C) is easy to control which plants mate with each other.
D) has only a few traits that appear in two easily distinguishable forms.
E) All answers are correct.

Question 6

Mendel called a masking trait

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

Question 7

When Mendel crossed short (tt)pea plants with short (tt)pea plants the offspring

A) were all tall.
B) were a mix of tall and short.
C) were nonexistent.
D) were all short.
E) No answer is correct.

Question 8

Of all the people who have studied inheritance,the person who made the most lasting impression on the science of genetics is

A) Charles Darwin.
B) Robert Hooke.
C) King George III.
D) Frederick Griffith.
E) Gregor Mendel.

Question 9

An allele that exerts its effects whenever it is present is

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

Question 10

When Mendel crossed tall (Tt)plants with tall (Tt)plants the offspring

A) did not grow and reproduce.
B) were always short.
C) were always tall.
D) were always medium height.
E) were mostly tall individuals and a few short individuals.

Question 11

The "P" in "P generation" refers to

A) pure breeding.
B) parental.
C) potential offspring.
D) recessive allele.
E) All answers are correct.

Question 12

If the two alleles for a particular gene are identical the gene pair is

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

Question 13

In humans,alleles for a gene locus on autosomes are inherited from

A) females only (mothers).
B) males only (fathers).
C) males and females (one allele from each parent).
D) males and females (two alleles from each parent).
E) No answer is correct.

Question 14

In the study of genetics,the offspring of the P generation are referred to as the

A) wild type generation.
B) F1 generation.
C) genotype.
D) F2 generation.
E) phenotype.

Question 15

Recessive alleles seem to vanish in some generations and reappear in later generations because they

A) cannot be expressed in males.
B) are masked by a dominant allele.
C) cannot be expressed in females.
D) cannot be expressed in successive generations.
E) are lost by mutation.

Question 16

If an individual is homozygous for a particular trait

A) each parent contributed a different allele for that trait.
B) one parent contributed two different alleles for that trait.
C) each parent contributed the same allele for that trait.
D) one parent contributed two copies of the same allele for that trait.
E) a mutation must have occurred.

Question 17

If an individual is heterozygous for a particular trait

A) each parent contributed a different allele for that trait.
B) each parent contributed the same allele for that trait.
C) one parent contributed two different alleles for that trait.
D) one parent contributed two copies of the same allele for that trait.
E) a mutation must have occurred.

Question 18

A portion of DNA that encodes a specific protein is a

A) gene.
B) chromosome.
C) chromatid.
D) centromere.
E) kinetochore.

Question 19

The most common allele,genotype,or phenotype in a population is referred to as the

A) wild type.
B) dominant population.
C) recessive population.
D) P generation.
E) F1 generation.

Question 20

If the two alleles for a particular gene are different the gene pair is

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

Question 21

A test cross is a mating of an individual with an unknown genotype and an individual that

A) is heterozygous.
B) is homozygous dominant.
C) is homozygous recessive.
D) has any known genotype.
E) is the wild type.

Question 22

A scientist wants to perform a monohybrid cross for stem length in pea plants that will show all possible genotypes in the progeny.Which pea plants will they cross?

A) ttgg x ttgg
B) tt x tt
C) TT x TT
D) TTGG x TTGG
E) Tt x Tt

Question 23

Traits that depend on more than one gene are

A) polygenic.
B) pleiotropic.
C) codominant.
D) recessive.
E) incomplete dominant traits.

Question 24

Autosomes

A) are chromosomes that are the same for both sexes.
B) include the Y chromosome in humans.
C) include the X chromosome in humans.
D) are the sex chromosomes.
E) All answers are correct.

Question 25

In the ABO blood type system,the Iᴬ allele is ________ with the Iᴮ allele.

A) dominant
B) codominant
C) recessive
D) homologous
E) heterologous

Question 26

An example of a monohybrid cross would be

A) an individual that is homozygous dominant for one trait undergoing self-fertilization.
B) a mating between two individuals that are heterozygous for two traits.
C) an individual that is homozygous recessive for one trait undergoing self-fertilization.
D) a mating between two individuals that are heterozygous for one trait.
E) an individual that is homozygous recessive for two traits undergoing self-fertilization.

Question 27

A gene that produces a protein important in more than one biochemical pathway is

A) dominant.
B) recessive.
C) pleiotropic.
D) codominant.
E) incomplete dominant.

Question 28

If any of the traits that Mendel worked with were linked genes,his dihybrid crosses would have

A) not yielded the phenotypic ratio of 9:3:3:1.
B) produced more offspring.
C) produced fewer offspring.
D) exhibited the phenotypic ratio of 9:3:3:1.
E) produced sterile offspring.

Question 29

A pea plant with (Tt)as its genotype should be referred to as

A) the wild type.
B) homozygous dominant.
C) heterozygous.
D) homozygous recessive.
E) mutant.

Question 30

If the heterozygous phenotype is intermediate between that of the homozygotes,this is called

A) codominance.
B) independent assortment.
C) linkage.
D) incomplete dominance.
E) polygenic.

Question 31

If all the offspring show the dominant phenotype in a test cross,then the individual with the unknown genotype was

A) heterozygous.
B) homozygous dominant.
C) homozygous recessive.
D) a clone of the other test cross individual.
E) heterozygous recessive.

Question 32

Linked genes,by definition,are genes that

A) are found on the same chromosome.
B) have no alleles.
C) are found in the same species.
D) have more alleles than usual.
E) are found in different daughter cells.

Question 33

The statement that segregation of alleles for a gene on one chromosome does not influence the segregation of alleles for a gene on another chromosome during gamete formation is Mendel's law of

A) independent assortment.
B) random fertilization.
C) population dynamics.
D) crossing over.
E) segregation.

Question 34

A dihybrid cross would be a mating between two individuals that are both

A) homozygous recessive for one gene.
B) homozygous dominant for two genes.
C) homozygous recessive for two genes.
D) heterozygous for one gene.
E) heterozygous for two genes.

Question 35

In the ABO blood type system the alleles Iᴬ,Iᴮ,and i produce

A) three phenotypes.
B) two phenotypes.
C) one phenotype.
D) four phenotypes.
E) type A and type B blood types only.

Question 36

Mendel's monohybrid cross of tall parents,each with the genotype Tt,resulted in a tall to short ratio of

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

Question 37

Diagrams of gene order and spacing on chromosomes are

A) genotypes and phenotypes.
B) phenotypes.
C) linkage maps.
D) genotypes.
E) metabolic maps.

Question 38

The alleles of each gene packaged into separate gametes summarizes Mendel's law of

A) segregation.
B) random fertilization.
C) population dynamics.
D) crossing over.
E) independent assortment.

Question 39

Crossing over is more likely to separate genes on a chromosome if they are

A) close together.
B) far apart.
C) recessive genes.
D) dominant genes.
E) mutated genes.

Question 40

Recombinant chromosomes have a mix of paternal and maternal alleles due to

A) random fertilization.
B) linkage.
C) independent assortment.
D) crossing over.
E) mutation.

Question 41

If you cross two heterozygous Yy pea plants,what proportion of the offspring will be the dominant color yellow?

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

Question 42

Diagrams depicting family relationships and phenotypes for a genetic disorder are

A) linkage maps.
B) pedigree charts.
C) genotype maps.
D) Punnett squares.
E) bell-shaped curves.

Question 43

A male expresses

A) only the dominant alleles on his X chromosome.
B) both the dominant and recessive alleles on his X chromosome.
C) only the homozygous recessive alleles on his X chromosome.
D) none of the alleles on his X chromosome.
E) only the homozygous dominant alleles on his X chromosome.

Question 44

Hemophilia A is caused by

A) an X-linked recessive disorder.
B) a Y-linked recessive disorder.
C) a defective neuron response.
D) an X-linked dominant disorder.
E) a Y-linked dominant disorder.

Question 45

Females who are "carriers" for hemophilia

A) usually do not show symptoms of hemophilia but pass the allele for hemophilia to all of their offspring.
B) pass the allele for hemophilia to all of their sons.
C) usually show symptoms of hemophilia but do not pass the allele for hemophilia to their offspring.
D) usually show symptoms of hemophilia and pass the allele for hemophilia to all of their offspring.
E) usually do not show symptoms of hemophilia.

Question 46

In pedigree charts,autosomal dominant disorders typically

A) appear only in males.
B) appear only in females.
C) appear in every generation.
D) seem to disappear in one generation, only to reappear in the next generation.
E) occur every third generation.

Question 47

Homologous chromosomes have

A) the same genes but can have different alleles.
B) the same genes and alleles.
C) different genes and alleles.
D) different genes, but can have the same alleles.

Question 48

If a genetic counselor examines a pedigree chart and notices an occurrence of a disease in every generation,the counselor would assume that the disease was caused by

A) a new mutation.
B) an autosomal recessive disorder.
C) a chromosomal abnormality.
D) an autosomal dominant disorder.
E) having an extra set of chromosomes.

Question 49

The chromosome that has the genes that determine whether a human is male or female is 

A) the X chromosome.
B) chromosome number 21.
C) the group of autosomes known as the SRY group.
D) chromosome number 22.
E) the Y chromosome.

Question 50

A person has a recessive,faulty allele for a disease,but the person does not have the disease since they also have a normal dominant allele.This person

A) is homozygous for the disease.
B) cannot produce gametes.
C) is termed a carrier.
D) is termed a linkage group.
E) has the disease but cannot pass this disease to their offspring.

Question 51

Having the alleles Tt is

A) a phenotype.
B) linkage.
C) a genotype.
D) a gene.
E) a locus.

Question 52

If a diploid cell has 14 chromosomes,it will have

A) 14 pairs of homologous chromosomes.
B) 7 pairs of homologous chromatids.
C) 14 pairs of homologous chromatids.
D) 7 pairs of homologous chromosomes.
E) 14 alleles.

Question 53

To inherit an autosomal recessive disorder requires that the person receive the allele leading to the disease from

A) the father only.
B) the mother only.
C) only the parent having the disease.
D) only one parent who is homozygous recessive for the disease.
E) both parents.

Question 54

If you cross two heterozygous (Yy)pea plants,what proportion of the offspring will be heterozygous?

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

Question 55

In pedigree charts,autosomal recessive disorders typically

A) appear in every generation.
B) appear only in males.
C) appear only in females.
D) may disappear in one generation and reappear in the next generation.
E) occur every third generation.

Question 56

Yellow peas are an example of

A) a phenotype.
B) a genotype.
C) an allele.
D) a gene.
E) a locus.

Question 57

If you cross two pea plants,one with green peas and the other with yellow peas,and all of the offspring have yellow peas,you conclude

A) green is dominant over yellow.
B) yellow and green are codominant.
C) yellow is incompletely dominant over green.
D) yellow is dominant over green.
E) color is random in pea plants.

Question 58

If you cross two pea plants,one with green peas and the other with yellow peas,and all of the offspring have yellow peas,you conclude

A) the yellow parent was homozygous for the recessive allele.
B) the green parent was homozygous for the dominant allele.
C) the yellow parent was homozygous for the dominant allele.
D) the green parent was heterozygous.
E) the yellow parent was heterozygous.

Question 59

A single chromosome has

A) multiple genes each with a single allele.
B) multiple genes each with multiple alleles.
C) a single gene with a single allele.
D) a single gene with multiple alleles.
E) No answer is correct.

Question 60

To inherit an autosomal dominant disorder a person could receive the allele leading to the disease from

A) the father only, not the mother.
B) the mother only, not the father.
C) the mother or the father.
D) the parent who does not exhibit the disease.
E) All answers are correct.

Question 61

Which gametes can a RrYy plant produce?

A) Rr or Yy
B) RY or ry
C) RrYy
D) RY, Ry, rY, or ry
E) R or r

Question 62

On a diagram of linked genes on a chromosome,the distance between the genes would be based on the frequency of crossing over between the genes during meiosis.

Question 63

A recessive allele is one whose effect is masked if a dominant allele is also present.

Question 64

If you cross RrYy and RRyy pea plants,what fraction of the offspring will have round yellow peas? R=round,r=wrinkled,Y=yellow,y=green

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

Question 65

Which gametes can a RRyy plant produce?

A) RR or yy
B) Ry
C) RY or ry
D) RRyy
E) R or y

Question 66

If you cross RrYy and RRyy pea plants,what fraction of the offspring will have yellow peas? R=round,r=wrinkled,Y=yellow,y=green

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

Question 67

The most common allele for any trait is always the dominant allele.

Question 68

In humans skin color widely varies.This is because skin color is

A) a polygenic trait.
B) influenced by environmental changes like improvements in diet.
C) influenced by an X-linked gene.
D) influenced by a Y-linked gene.
E) influenced by crossing over.

Question 69

If the probability of one genetic event is 1/2 and of another 1/6,then the probability of both occurring is 1/12.

Question 70

Genotypes are the outward expression of an allele combination.

Question 71

If you cross RrYy and RRyy pea plants,what fraction of the offspring will have round peas? R=round,r=wrinkled,Y=yellow,y=green

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

Question 72

Adult female bollworm moths lay eggs on cotton bolls.These eggs then hatch and grow into caterpillars that eat the seeds of the boll.The eggs and sperm are produced by

A) meiosis.
B) mitosis.
C) fertilization.
D) crossing over.
E) mutation.

Question 73

Hemophilia A is an X-linked recessive disorder.What is the probability that a son will have hemophilia if the parents are a normal man and a woman who is a carrier?

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

Question 74

A gene that affects flower color,root length,and leaf shape is pleiotropic.

Question 75

Average heights of American men and women have increased steadily since the 1940s.The best explanation for this observation is that height is

A) a polygenic trait.
B) influenced by an X-linked gene.
C) influenced by environmental changes like improvements in diet.
D) influenced by a Y-linked gene.
E) influenced by crossing over.

Question 76

Each gamete arises from a diploid cell containing two sets of homologous chromosomes.

Question 77

Mendel's law of segregation states that the two alleles of each gene are packaged into separate gametes.

Question 78

In an inherited form of high cholesterol,HH individuals have a blood cholesterol level greater than 500mg/dL,RH individuals are near 300mg/dL,and normal (RR)cholesterol levels should be less than 200mg/dL.The H allele is ________ to the R allele.

A) codominant
B) dominant
C) recessive
D) homozygous
E) incompletely dominant

Question 79

A man with type A blood and a woman with type B blood have a child with type O blood.What are the genotypes of the man and woman?

A) Iᴬ ᶦ, and Iᴮ ᶦ
B) both are i i
C) Iᴬ ᴵᴬ, and Iᴮ ᴵᴮ
D) Iᴬ ᶦ, and i i
E) i i, and Iᴮ ᶦ
ᴬⁿˢʷᵉʳ: A

Question 80

If two genes are linked,they will appear to violate Mendel's law of segregation.