Deck 12: Patterns of Inheritance

Question 1

An allele that is present but unexpressed is

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

Answer 1

E

Question 2

The Principle of ________ states that the 2 alleles present at each gene locus separate from one another during gamete formation and remain distinct.

A)Alleles
B)Segregation
C)Crossing over
D)Dominance
E)Independent assortment

Answer 2

B

Question 3

Mendel chose the garden pea for his work on inheritance for which of the following reasons? Check all that apply.

A)Some traits in pea plants are controlled by one dominant allele and one recessive allele.
B)Earlier investigators had shown segregation among the offspring.
C)A large number of true breeding varieties were available.
D)The generation time was short; many offspring can be grown easily.
E)He could choose to self- or cross-pollinate.

Answer 3

B,C,D,E

Question 4

In modern terminology,Mendel's heredity "factors" are called

A)DNA.
B)chromosomes.
C)genes.
D)RNA.

Question 5

In a heterozygous individual,the allele being expressed is

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

Question 6

During his experiments with pea plants,Mendel referred to the trait that was expressed in the F₁ or first filial generation as

A)recessive.
B)dominant.
C)codominant.
D)independent.
E)homozygous.

Question 7

Mendel used the garden ________ plant for his studies on inheritance.

A)lily
B)carrot
C)onion
D)pea

Question 8

In Mendel's experiments on seed color in pea plants,when a dominant yellow seed-bearing plant was crossed with a recessive green seed-bearing plant,what was the approximate phenotypic ratio among the F₂ generation?

A)1 yellow: 3 green
B)1 yellow: 1 green
C)3 yellow: 1 green
D)all yellow
E)9:3:3:1

Question 9

Knight followed up on attempts of English farmers to improve varieties of agriculture with his studies on garden peas.When he crossed two true-breeding varieties,he found all of the following: Check all that apply.

A)All the F₁ offspring had the dominant trait.
B)If both parents have the same trait,then all of their offspring will also have that trait.
C)Some F₂ offspring had the dominant trait and some had the recessive trait.
D)Among the F₂ offspring,more had the dominant trait and fewer had the recessive trait.

Question 10

Mendel's understanding of the inheritance of traits in peas,expressed in modern language,included: Check all that apply.

A)parents transmit information encoded in genes.
B)each individual contains two genes for each trait.
C)not all genes are identical; alternative forms (alleles)exist.
D)each of the alleles present in an individual is discrete.
E)if a given allele is present,its effects will be seen in the individual.

Question 11

Mendel demonstrated which of the following about inherited traits? Check all that apply.

A)traits can be hidden in some generations,but subsequently reappear unchanged in future generations.
B)traits segregate among the offspring of a cross.
C)certain traits are more likely to appear than their alternatives.
D)some traits show blending inheritance.
E)parents that both have the same trait can have offspring with an alternative trait.

Question 12

A diploid organism that has two identical alleles for a given trait is called ________ for that trait.

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

Question 13

Alternate forms of the same gene are called

A)homologues.
B)genotypes.
C)cofactors.
D)alleles.

Question 14

The observable expression of the genes present in an organism is called its

A)phenotype.
B)genotype.
C)pedigree.
D)karyotype.

Question 15

The first detailed and quantitative studies on inheritance were carried out by an Austrian monk named ________.

A)Mendel
B)Darwin
C)Mendeleev
D)Benedict

Question 16

The phenotypic ratio for the F₁ generation that results from a testcross between a homozygous recessive individual and a heterozygous individual is

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

Question 17

Individuals that have 2 alleles for most gene loci are best described as

A)haploid.
B)diploid.
C)dihybrid.
D)homozygous.
E)heterozygous.

Question 18

Mendel used the ________ to determine whether an individual with the dominant phenotype was homozygous or heterozygous for that trait.

A)backcross
B)testcross
C)dihybrid cross
D)F₂ generation
E)double cross

Question 19

An allele for a particular trait that is only expressed in the presence of a second copy of the same allele is called

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

Question 20

If fertilization involves two gametes that contain different alleles of a given gene,the resulting offspring is

A)dihybrid.
B)haploid.
C)heterozygous.
D)homozygous.
E)polygenic.

Question 21

Height is a trait that shows continuous variation in humans.In pea plants,on the other hand,the tall allele is dominant over the short allele and there are no intermediate heights.What is the best explanation for this difference?

A)The alleles that control height in pea plants are epistatic.
B)The alleles that control height in pea plants are pleiotropic.
C)The alleles that control height in humans are pleiotropic.
D)Height is a polygenic trait in humans.
E)Height is a polygenic trait in pea plants.

Question 22

The independent assortment of allele pairs is due to

A)the independent segregation of homologous chromosome pairs during anaphase II.
B)the random combination of gametes during fertilization.
C)the independent segregation of sister chromatid pairs during anaphase I.
D)the independent segregation of non-sister chromatid pairs during anaphase II.
E)the independent segregation of homologous chromosome pairs during anaphase I.

Question 23

An extensive study was conducted on identical twins who were separated at birth.Among other things,the study showed that the individual from each pair who received better nutrition during childhood tended to score higher on standardized intelligence tests.This can best be described as an example of how

A)mutation alters phenotype.
B)environment alters phenotype.
C)environment alters genotype.
D)mutation alters genotype.
E)pleiotropic genes affect more than one trait.

Question 24

The allelic make up of a cell or individual is referred to as its

A)blueprint.
B)genotype.
C)phenotype.
D)pedigree.

Question 25

If a single gene has 3 or more alternative forms,this is called

A)pleiotropy.
B)multiple alleles.
C)epistasis.
D)blending inheritance.
E)codominance.

Question 26

When Mendel crossed purple-flowered pea plants with white-flowered pea plants,he never got offspring with flowers that had an intermediate color.This was counter to the theory of

A)independent assortment.
B)blending inheritance.
C)direct transmission of traits.
D)segregation of alleles.
E)continuous variation of traits.

Question 27

A person who has lost a large amount of blood but is still alive is found in a wrecked automobile under a highway bridge.Several people are helping the paramedics load the victim into the ambulance.After the ambulance has departed for the hospital,you overhear the following conversation from the persons who helped the paramedics."I am certain that when that guy gets to the hospital,they will transfuse him with any blood that they have in the blood bank since he has lost so much blood." The other person says,"Yeah,I bet you're right!" Having had a biology course,you know which blood could be safely given to anyone.Select it below.

A)A
B)B
C)AB
D)O

Question 28

The observable outward manifestation of the genes of an individual is referred to as its

A)blueprint.
B)genotype.
C)phenotype.
D)genetic map.
E)pedigree.

Question 29

Based on his monohybrid crosses,Mendel's proposed which of the following? Check all that apply.

A)Alternative forms of a trait are encoded by alternative alleles.
B)The 2 alleles for a given trait separate when gametes form.
C)Each allele has an equal probability of being passed on to the gametes.
D)Allele pairs segregate independently of each other.
E)Diploid individuals have 2 alleles for each trait.

Question 30

Irene knows her blood type is A,but William does not know his blood type.However,William knows that his mother and father both had blood type B.Irene and William's first child is a boy with type O blood.Based on this information,William's blood type could be

A)B only
B)either B or O
C)O only
D)either AB or O
E)A only

Question 31

Let P = purple flowers and p = white,and T = tall plants and t = dwarf.If the uppercase letters represent the dominant alleles,what is the phenotype of a plant with the genotype PpTt?

A)purple flowers,tall
B)purple flowers,dwarf
C)white flowers,tall
D)white flowers,dwarf
E)pale purple flowers,intermediate height

Question 32

ABO blood group determination is an example of

A)epistasis.
B)incomplete dominance.
C)polygenic inheritance.
D)multiple alleles.
E)pleiotropy.

Question 33

A cross where we follow the inheritance of 2 pairs of alleles is called

A)homozygous.
B)monohybrid.
C)dihybrid.
D)heterozygous.
E)diallelic.

Question 34

What type of cross is used to determine if an individual with the dominant form of a trait is homozygous or heterozygous?

A)double cross
B)dihybrid cross
C)reciprocal cross
D)test cross
E)back cross

Question 35

Sometimes,when Mendel crossed two pea plants with each other,he obtained a phenotypic ratio of 3:1 purple-flowered pea plants to white-flowered pea plants.These results are consistent with which set of parents?

A)homozygous purple pea plant and homozygous white pea plant
B)heterozygous purple pea plant and homozygous white pea plant
C)heterozygous purple pea plant and homozygous purple pea plant
D)heterozygous purple pea plant and heterozygous purple pea plant

Question 36

Let P = purple flowers and p = white,and T = tall plants and t = dwarf.What are the genotypes of the gametes that are produced by a plant that is heterozygous for both traits?

A)PpTt only
B)PT and pt
C)P,p,T,and t
D)PT,Pt,pT,and pt
E)Tt,TT,tt,Pp,PP,and pp

Question 37

Sometimes,one gene pair will interfere with the expression of a second gene pair in an interaction called

A)incomplete dominance.
B)codominance.
C)blending inheritance.
D)pleiotropy.
E)epistasis.

Question 38

If an individual allele has more than one effect on the phenotype,this is called

A)pleiotropy.
B)epistasis.
C)blending inheritance.
D)multiple alleles.
E)polygenic inheritance.

Question 39

Mendel's Principle of Independent Assortment states that different pairs of

A)non-homologous chromosomes segregate independently of each other.
B)sister chromatids segregate independently of each other.
C)non-sister chromatids segregate independently of each other.
D)alleles segregate independently of each other.
E)gametes segregate independently of each other.

Question 40

Let P = purple flowers and p = white,and T = tall plants and t = dwarf.Of the 16 possible gamete combinations in the dihybrid cross between 2 double heterozygotes,how many would produce the phenotype white,tall?

A)none
B)1
C)3
D)9
E)16

Question 41

The ________ of an organism refers to the alleles that are present.

A)genotype
B)karyotype
C)pedigree
D)phenotype
E)pleiotropy

Question 42

In rabbits,there is a gene that controls ear length,with a dominant allele "T" for long ears and a recessive allele "t" for short ears.At another gene locus,there are alleles "B" for black coat and "W" for white coat.Neither the B or W allele is dominant,and BW produces a gray coat.These two allele pairs assort independently.If a gray rabbit that is heterozygous at the gene locus controlling ear length is mated with a white rabbit that is also heterozygous at the gene locus controlling ear length,what proportion of the long-eared offspring will be homozygous for the long-eared trait?

A)1/8
B)1/4
C)1/3
D)1/2

Question 43

A scientist has an uncharacterized pea plant.She wants to determine the plant's genotype for seed color.In order to be certain that she will get conclusive results from a single cross,with what plant could she cross it? Check all that apply.

A)a green-seeded pea plant (yy)
B)a yellow-seeded pea plant (YY)
C)itself

Question 44

The observable expression of the genes present is called

A)genotype
B)karyotype
C)epistasis
D)phenotype

Question 45

In mice,the allele for black fur is dominant to the allele for brown fur.If a male heterozygous black mouse is crossed with a female brown mouse,what percentage of the F₁ offspring do you predict will be homozygous? (Enter the number only without the percent sign.For example,enter 100% as 100 and enter 12.5% as 12.5)

Question 46

A diploid individual carrying two different alleles at a given gene locus is called

A)homologous.
B)heterozygous.
C)homozygous.
D)polygenic.

Question 47

Mendel performed reciprocal crosses in which he used pollen from a white-flowered plant to fertilize a purple-flowered plant and pollen from a purple-flowered plant to fertilize a white-flowered plant.What did these reciprocal crosses demonstrate?

A)The female gamete made a larger genetic contribution to the offspring than the male gamete.
B)Each parent made an equal genetic contribution to the offspring.
C)Flower color is a sex-linked trait.
D)The traits of flower color and sex assort independently.
E)The male gamete made a larger genetic contribution to the offspring than the female gamete.

Question 48

In humans,the sickle-cell trait is caused by a single defective allele,but sickle-cell disease only occurs in individuals that are homozygous for the sickle-cell allele.A man and woman each carry the trait,but do not have sickle-cell disease.What is the probability that their first two children will both have sickle-cell disease?

A)1/16
B)1/8
C)1/4
D)3/8
E)1/2

Question 49

A male fruit fly has the genotype PpYYrrTt.In terms of these 4 allele pairs,how many different types of gametes can he form?

A)2
B)4
C)8
D)16

Question 50

A diploid individual carrying two identical alleles at a given gene locus is called

A)homologous.
B)heterozygous.
C)homozygous.
D)dihybrid.

Question 51

As a genetic counselor,you are constructing a human pedigree for a particular disease.You note that every generation shows the trait,suggesting that the trait is

A)sex-linked.
B)recessive.
C)dominant.
D)polygenic.
E)pleiotropic.

Question 52

Pedigrees are useful to geneticists because they can help determine: Check all that apply.

A)the mode of inheritance for a particular trait.
B)the genotype of a particular individual.
C)the probability that future offspring will inherit a particular trait.
D)whether a particular trait is dominant or recessive.

Question 53

Before Mendel's experiments with pea plants,which ideas formed the basis for most thinking about heredity? Check all that apply.

A)species gradually change over time
B)the traits of both parents are blended together in their offspring
C)heredity occurs within species
D)some traits are dominant and some are recessive
E)traits are transmitted directly from parents to offspring

Question 54

In watermelons,the gene for green color is dominant over its allele for striped color.At another gene locus,the gene for short shape is dominant over its allele for long shape.These two allele pairs assort independently.If a plant with long,striped fruit is crossed with a plant that is heterozygous for both of these traits,what percentage of the offspring do you expect will be short and green? (Enter the number only without the percent sign.For example,enter 100% as 100 and enter 12.5% as 12.5)

Question 55

Achondroplasia is a common form of dwarfism caused by an autosomal dominant mutation in the fibroblast growth factor receptor 3 (FGFR3)gene.Two copies of the mutant gene are invariably fatal before or shortly after birth.If a person with achondroplasia marries a person of normal height,what is the probability that both their first child and second child will have achondroplasia?

A)1/8
B)1/4
C)1/2
D)1

Question 56

In rabbits,there is a gene that controls ear length,with a dominant allele "T" for long ears and a recessive allele "t" for short ears.At another gene locus,there are alleles "B" for black coat and "W" for white coat.Neither the B or W allele is dominant,and BW produces a gray coat.These two allele pairs assort independently.If a gray rabbit that is heterozygous at the gene locus controlling ear length is mated with a white rabbit that is also heterozygous at the gene locus controlling ear length,what is the probability that their first offspring will be gray with long ears?

A)1/16
B)3/16
C)1/8
D)3/8
E)1/2

Question 57

Let R = red pigment and r = no pigment.In carnations,RR offspring make a lot of red pigment,rr offspring make no pigment and Rr offspring make a small amount of red pigment,thus appearing pink.Pink carnations are therefore an example of

A)codominance.
B)incomplete dominance.
C)epistasis.
D)pleiotropy.

Question 58

A Punnett square is generally used to

A)determine the genotype of each parent from its phenotype.
B)determine the phenotype of each parent from its genotype.
C)predict the genotypic ratio among the offspring.
D)predict the number of offspring that will exhibit each genotype.

Question 59

You toss a coin twice.Because the outcome of the first toss does not affect the outcome of the second toss,these 2 events are called

A)mutually exclusive.
B)independent.
C)dependent.
D)random.

Question 60

If you are tossing a six-sided die,what is the probability of getting either a 1 or a 2 on your first toss AND a 1 or a 2 on your second toss?

A)1/18
B)1/9
C)1/6
D)1/3
E)2/3

Question 61

Three babies were recently mixed up in a hospital.Based on the data in the table above,the couple with blood types A and B are the actual parents of the child with blood type

A)O
B)B
C)AB
D)None of these babies could be the child of the couple with blood types A and B.

Question 62

Consider the cross AaBbCcddEe X AABBccDDEe.If these 5 allele pairs all assort independently,then the probability that any individual offspring will have the genotype AABBccDdEe is 1 out of

Question 63

A woman with blood type O has a child with blood type O.She claims that a man named Ralph is the child's father.Her claim would be proven false if Ralph has blood type: Check all that apply.

A)O
B)A
C)B
D)AB

Question 64

Two parents each have blood type AB,and their first child is blood type AB.What is the probability that their second child will have blood type AB? (Express the probability as a percent.Enter the number only without the percent sign.For example,enter 100% as 100 and enter 12.5% as 12.5)