Deck 11: Observing Patterns in Inherited Traits

Question 1

Which of the following is NOT a characteristic of the plants with which Mendel worked?

A)They produce male and female parts.
B)They exhibit blending inheritance.
C)They normally self-fertilize.
D)They have many different contrasting traits and exhibit some pure-breeding varieties.
E)They can easily be cross-fertilized by human manipulation.

Answer 1

B

Question 2

Diploid organisms

A)have corresponding alleles on homologous chromosomes.
B)are usually the result of the fusion of two haploid gametes.
C)have two sets of chromosomes.
D)have pairs of homologous chromosomes.
E)have all of these qualities.

Answer 2

E

Question 3

From his monohybrid experiments, Mendel determined that __________is the dominant form.

A)wrinkled seed
B)yellow pod
C)dwarf plant height
D)yellow seed
E)white flower

Answer 3

D

Question 4

Hybrid organisms produced from a cross between two pure-breeding organisms belong to which generation?

A)P₁
B)G₁
C)A₁
D)F₁
E)F₂

Question 5

Which of the following descriptions of Mendel is INCORRECT?

A)He was simply lucky to work out the laws of genetics.
B)He focused on contrasting phenotypic characteristics.
C)He demonstrated that the blending theory of inheritance was wrong.
D)He kept exact mathematical data and was one of the first scientists to analyze results numerically.
E)He was a monk, a science teacher, and a plant breeder.

Question 6

Gene A occurs on chromosome 5, gene B is on chromosome 21.Therefore, these two portions of the chromosomes CANNOT be

A)genes.
B)dominant.
C)loci.
D)alleles.
E)recessive.

Question 7

In his experiments with pea plants, Mendel removed which part of the plant to prevent unwanted fertilizations?

A)flowers
B)petals
C)pistils
D)stamens
E)stigmas

Question 8

Various forms of a single gene at a given locus is called

A)kinetochores.
B)alleles.
C)autosomes.
D)loci.
E)chromatids.

Question 9

Which organism did Mendel utilize to work out the laws of segregation and independent assortment?

A)the fruit fly
B)the rose
C)the garden pea
D)the chicken
E)E.coli

Question 10

The most accurate description of an organism with genotype AaBb is

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

Question 11

Which of the following is TRUE of melanosomes?

A)All people have about the same number of melanosomes.
B)The color of the melanosome dictates skin color.
C)Excess sunlight decreases melanin.
D)White Europeans lack melanosomes.
E)All of these are true.

Question 12

Which of the following is a homozygous genotype?

A)AaBB
B)aABB
C)aaBB
D)aaBb
E)AaBb

Question 13

Which of the following statements about Mendel is false?

A)He did not know about chromosomes.
B)He was not aware of Darwin's theory of evolution.
C)He was well trained in agriculture and mathematics.
D)His work was widely recognized..
E)His work established a basic understanding of the principles of heredity.

Question 14

The letter B in the above figure represents which of the following?

A)carpels
B)stamen
C)eggs
D)fertilized pea seeds
E)none of these are correct

Question 15

Which of the following statements is true?

A)Darwin did not know what mechanisms were responsible for the variation he saw.
B)The blending theory of inheritance provides excellent support for evolution.
C)Darwin received Mendel's paper but did not understand its significance.
D)The explanation for genetics had no implications for evolution.
E)All of these are true.

Question 16

During Mendel's lifetime, most people believed that

A)all genetic traits bred true.
B)only certain forms of domesticated plants and animals bred true.
C)the characteristics of parents were blended in the offspring.
D)the mother contributed all the hereditary material for the new generation.
E)the father contributed all the hereditary material for the new generation.

Question 17

Over __________ genes are involved in skin color determination.

A)100
B)40
C)10
D)1
E)1000

Question 18

The pea plant was an excellent choice for Mendel's experiments because

A)true-breeding varieties were available.
B)the plant can self-fertilize.
C)it can be cross-fertilized.
D)true-breeding varieties were available, and it can be cross-fertilized.
E)true-breeding varieties were available, the plant can self-fertilize, and it can be cross-fertilized.

Question 19

Mendel's study of genetics differed from studies of his contemporaries' because he

A)used only pure-breeding parents.
B)examined several different traits at the same time.
C)kept careful records and analyzed the data statistically.
D)worked on plants rather than animals.
E)confirmed the blending theory of inheritance.

Question 20

A gene locus is

A)a recessive gene.
B)an unmatched allele.
C)a sex chromosome.
D)the location of an allele on a chromosome.
E)a dominant gene.

Question 21

If short hair (L) is dominant to long hair (l), then to determine the genotype of a short-haired animal it should be crossed with

A)LL.
B)Ll.
C)ll.
D)all of these.
E)none of these.

Question 22

If tall (D) is dominant to dwarf (d), and two homozygous varieties DD and dd are crossed, then what kind of progeny will be produced?

A)all intermediate forms
B)all tall
C)all dwarf
D)1/2 tall, 1/2 dwarf
E)3/4 tall, 1/4 dwarf

Question 23

A testcross consists of a cross

A)of two pure-breeding forms to find out which form of a gene is dominant.
B)between two unknown forms to determine their genotypes.
C)between an offspring and its homozygous dominant parent.
D)of an organism of dominant phenotype but unknown genotype to an individual that is homozygous recessive for that trait.
E)of two F₂ individuals to produce an F₃ generation.

Question 24

If all offspring of a cross have the genotype Aa, the parents of the cross are most likely

A)AA x aa.
B)Aa x Aa.
C)Aa x aa.
D)AA x Aa.
E)none of these.

Question 25

According to Mendel, what kinds of genes "disappear" in F₁ pea plants?

A)sex-linked
B)dominant
C)recessive
D)codominant
E)lethal

Question 26

For Mendel's explanation of inheritance to be correct,

A)the genes for the traits he studied have to be located on the same chromosome.
B)the combination of gametes at fertilization has to be due to chance.
C)genes cannot be transmitted independently of each other.
D)only diploid organisms demonstrate inheritance patterns.
E)none of these apply.

Question 27

The F₂ phenotypic ratio of a monohybrid cross is

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

Question 28

If R is dominant to r, the offspring of the cross of RR with rr will

A)be homozygous.
B)display the same phenotype as the RR parent.
C)display the same phenotype as the rr parent.
D)have the same genotype as the RR parent.
E)have the same genotype as the rr parent.

Question 29

If short hair (L) is dominant to long hair (l), then what fraction of the offspring produced by a cross of Ll x ll will be homozygous dominant?

A)1/2
B)1/4
C)1/3
D)none (no chance of this offspring)
E)none of these answers is correct

Question 30

The theory of segregation

A)concerns alleles governing two different traits.
B)applies only to linked genes.
C)applies only to sex-linked genes.
D)explains the behavior of a pair of alleles during meiosis.
E)none of these.

Question 31

The theory of segregation applies most specifically to events occurring in preparation of

A)offspring.
B)zygotes.
C)homologous chromosomes.
D)gametes.
E)loci.

Question 32

In a Punnett square, the letters within the little boxes represent

A)offspring genotypes.
B)parental genotypes.
C)gametes.
D)offspring phenotypes.
E)parental phenotypes.

Question 33

A testcross involves

A)two F₁ hybrids.
B)an F₁ hybrid and an F₂ offspring.
C)two parental organisms.
D)an F₁ hybrid and the homozygous dominant parent.
E)an organism of dominant phenotype but unknown genotype and an organism that is homozygous recessive for that trait.

Question 34

A homozygous dominant parent will produce

A)one type of gamete with this one homozygous allele.
B)two types of gamete with this one homozygous allele.
C)a mixture of gametes with both homozygous and recessive alleles.
D)a single gamete with a single mutant allele.
E)none of these.

Question 35

For monohybrid experiments, a testcross can result in which of the following ratios?

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

Question 36

Mendel found that pea plants expressing a recessive trait

A)were pure-breeding.
B)appeared only in the first generation of a cross between two pure-breeding plants expressing contrasting forms of a trait.
C)disappeared after the second generation.
D)could be produced only if one of the parents expressed the recessive trait.
E)were none of these.

Question 37

Using the illustration below and the assumption that half of a plant's sperm and eggs are a and half are A, one can predict that the chance of sperm a meeting egg A at fertilization is

A)1/2 x 1/2.
B)25 percent.
C)one out of four.
D)1/2.
E)all of these EXCEPT 1/2.

Question 38

Short hair (L) is dominant to long hair (l).If a short-haired animal of unknown origin is crossed with a long-haired animal and they produce one long-haired and one short-haired offspring, this indicates that

A)the short-haired animal is pure-breeding.
B)the short-haired animal is not pure-breeding.
C)the long-haired animal is not pure-breeding.
D)the long-haired animal is pure-breeding.
E)none of these can be determined with two offspring.

Question 39

If Mendel had not examined the __________ generation, he would not have discovered his theory of segregation.

A)P₁
B)H₁
C)A₁
D)F₁
E)F₂

Question 40

If short hair (L) is dominant to long hair (l), animals LL and Ll have the same

A)parents.
B)genotypes.
C)phenotypes.
D)alleles.
E)genes.

Question 41

A dihybrid cross of two contrasting pure-breeding organisms

A)produces homozygous offspring.
B)must produce a phenotype different from either pure-breeding parent.
C)results in the disappearance of the recessive traits in the first generation.
D)takes place only in the laboratory under precisely controlled conditions.
E)will result in the immediate formation of another pure-breeding variety.

Question 42

Who proposed the law of independent assortment?

A)Morgan
B)Mendel
C)Darwin
D)Cuvier
E)Flemming

Question 43

Mendel's theory of independent assortment states that

A)one allele is always dominant to another.
B)hereditary units from the male and female parents are blended in the offspring.
C)the two hereditary units that influence a certain trait segregate during gamete formation.
D)each hereditary unit is inherited separately from other hereditary units.
E)all of these are true.

Question 44

If a child has an AB blood type, the parents

A)must both have different blood types.
B)must be A and B, but not AB.
C)must both be AB.
D)can be any blood type.
E)can have different blood types, but neither can be blood type O.

Question 45

Which offspring in the illustration below are homozygous recessive for both traits?

A)A
B)B
C)C
D)D
E)none of these

Question 46

The theory of independent assortment

A)is not demonstrated in a monohybrid cross.
B)is illustrated by the behavior of linked genes.
C)indicates that the expression of one gene is independent of the action of another gene.
D)states that alleles for the same characteristic separate during meiosis.
E)is negated by the phenomenon of epistasis.

Question 47

Mendel would not have seen four different phenotypes in the F₂ generation of his dihybrid crosses if

A)the genes were on the same chromosomes.
B)the P₁ generation was homozygous.
C)purple was dominant to white.
D)more than two traits were traced.
E)all of these are true.

Question 48

The ABO blood types are controlled by

A)pleiotropy.
B)multiple alleles.
C)incomplete dominance.
D)codominance.
E)multiple alleles and codominance.

Question 49

Susan, a mother with type B blood, has a child with type O blood.She claims that Craig, who has type A blood, is the father.He claims that he cannot possibly be the father.Further blood tests ordered by the judge reveal that Craig is AA.The judge rules that

A)Susan is right, and Craig must pay child support.
B)Craig is right and doesn't have to pay child support.
C)Susan cannot be the real mother of the child; there must have been an error made at the hospital.
D)it is impossible to reach a decision based on the limited data available.
E)none of these is true.

Question 50

The ABO blood types have __________ different genotypes.

A)4
B)6
C)8
D)12
E)16

Question 51

Mendel's dihybrid crosses provided indirect evidence for all but which one of the following?

A)independent assortment
B)dominance
C)linkage
D)presence of two factors in parents and offspring
E)segregation of factors

Question 52

If a child belonged to blood type O, he or she could NOT have been produced by which set of parents?

A)type A mother and type B father
B)type A mother and type O father
C)type AB mother and type O father
D)type O mother and type O father
E)type O mother and type B father

Question 53

The usual F₂ phenotypic ratio of a dihybrid cross is

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

Question 54

All BUT which of these genotypes is a possible F₁ gamete for a dihybrid cross between AA BB with aa bb?

A)Aa
B)Ab
C)AB
D)aB
E)ab

Question 55

The number of different alleles for ABO blood types in the total human population is

A)4.
B)6.
C)9.
D)undetermined.
E)3.

Question 56

Blood types (A, B, and O) are controlled by

A)sex-linked genes.
B)linked genes.
C)incompletely dominant genes.
D)multiple alleles.
E)none of these.

Question 57

Which of the following statements about the F₂ generation produced in the dihybrid cross is NOT true?

A)All offspring with the same phenotype have the same genotype.
B)All offspring with the same genotype possess the same phenotype.
C)It is not possible to determine the genotype of some individuals by their phenotype.
D)It is possible to tell the genotype of some offspring by looking at their phenotypes.
E)Nine genotypes and four phenotypes are produced.

Question 58

An individual with a genetic makeup of aa BB is called

A)pure-breeding.
B)recessive.
C)hybrid.
D)dihybrid.
E)heterozygous.

Question 59

In __________, a pair of nonidentical alleles affecting two phenotypes for a given trait is both expressed at the same time in heterozygotes.

A)pleiotropy
B)polygenic inheritance
C)complete dominance
D)codominance
E)a multiple allele system

Question 60

Mendel's dihybrid crosses, but not his monohybrid crosses, show that

A)some genes are linked together.
B)the two alleles controlling a trait are divided equally among the gametes.
C)alleles for different traits are inherited independently.
D)one of the pair of alleles is dominant to the other.
E)the crossing of two different homozygous forms will not produce any offspring in the first generation that will look like either of the parents.

Question 61

Some dogs have erect ears; others have drooping ears.Some dogs bark when following a scent; others are silent.Erect ears and barking are due to dominant alleles located on different chromosomes.If two dihybrids are crossed,

A)the most common phenotype is drooping ears and barking.
B)all droopy-eared, silent offspring are pure-breeding.
C)the least common phenotype is drooping ears and barking.
D)there will be no phenotypes or genotypes that resemble the original parents.
E)there will be no offspring that resemble the F₁ generation.

Question 62

Which of the following would be an exception to the theory of independent assortment?

A)dominance
B)recessiveness
C)incomplete dominance
D)pleiotropy
E)linkage

Question 63

In cocker spaniels, black coat color (B) is dominant over red (b), and solid color (S) is dominant over spotted (s).If two dihybrids (Bb Ss) are crossed, which will be produced?

A)black and spotted pure-breeding forms
B)black and solid pure-breeding forms
C)red and solid pure-breeding forms
D)red and spotted pure-breeding forms
E)all of these

Question 64

Some dogs have erect ears; others have drooping ears.Some dogs bark when following a scent; others are silent.Erect ears and barking are due to dominant alleles located on different chromosomes.A dog homozygous for both dominant traits is mated to a droopy-eared, silent follower.The expected phenotypic ratio in the F₁ generation is

A)9:3:3:1.
B)100 percent of one phenotype.
C)1:1.
D)1:2:1.
E)none of these.

Question 65

In cocker spaniels, black coat color (B) is dominant over red (b), and solid color (S) is dominant over spotted (s).In the F₂ generation of a cross between BB ss with bb SS, what fraction of the offspring are expected to be black and spotted?

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

Question 66

In cocker spaniels, black coat color (B) is dominant over red (b), and solid color (S) is dominant over spotted (s).A cross of Bb Ss with bb ss will produce the phenotypic ratio

A)9:3:3:1.
B)1:1:1:1.
C)1:2:1.
D)3:1.
E)of none of these.

Question 67

Solid color allele is dominant to striped, and long hair allele is dominant to short hair in a laboratory animal.If the mating of a long, solid animal with a short, striped animal produces the maximum number of phenotypes, how many will be produced?

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

Question 68

Assume that short hair (L) is dominant to long hair (l) and black hair (B) is dominant to brown (b).If you find a black, short-haired animal, you can determine its genotype by crossing it to an animal with a genotype of

A)LL BB.
B)ll BB.
C)ll Bb.
D)ll bb.
E)LL bb.

Question 69

The illustration below shows the F₂ phenotypes from a monohybrid cross in snapdragons.What type of inheritance produces such an outcome?

A)complete dominance
B)incomplete dominance
C)multiple alleles
D)continuous variation
E)epistasis

Question 70

In cocker spaniels, black coat color (B) is dominant over red (b), and solid color (S) is dominant over spotted (s).If two dihybrids (Bb Ss) are crossed, the most common phenotype will be

A)black and solid.
B)black and spotted.
C)red and solid.
D)red and spotted.
E)none of these.

Question 71

The F₂ phenotypic ratio of a monohybrid cross involving a gene with incompletely dominant alleles is

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

Question 72

If one parent has type A blood and the other parent has type B, then which of the following is possible in the children?

A)only AB
B)A and AB
C)B and AB
D)A, B, AB, and O
E)only O

Question 73

In cocker spaniels, black coat color (B) is dominant over red (b), and solid color (S) is dominant over spotted (s).If two dihybrids (Bb Ss) are crossed, what fraction of the black, solid offspring will be homozygous?

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

Question 74

In cocker spaniels, black coat color (B) is dominant over red (b), and solid color (S) is dominant over spotted (s).If a red male is crossed with a black female to produce a red, spotted puppy, the genotypes of the parents (with male genotype first) will be

A)Bb Ss x Bb Ss.
B)bb Ss x Bb Ss.
C)bb ss x Bb Ss.
D)bb Ss x Bb ss.
E)Bb ss x Bb ss

Question 75

If a pure-breeding long-tail cat (LL) is crossed with a pure-breeding cat with no tail (rumpy, ll), and a cat with a short tail (stumpy) is produced, the simplest explanation is

A)a mutation.
B)an X-linked gene.
C)an incompletely dominant gene.
D)a lethal gene.
E)chromosomal aberration.

Question 76

In incomplete dominance,

A)one allele is not dominant to another allele.
B)the genotype can be determined by the phenotype.
C)the heterozygote is somewhat intermediate to the two homozygotes.
D)the intermediate phenotype may be the result of enzyme insufficiency.
E)all of these are true.

Question 77

The type of inheritance that suggests the concept of blending is

A)multiple alleles.
B)autosomal dominance.
C)codominance.
D)incomplete dominance.
E)codominance and incomplete dominance.

Question 78

In the second generation of a cross of DD RR with dd rr, the most common genotype will be

A)DD RR.
B)Dd RR.
C)Dd Rr.
D)dd RR.
E)dd Rr.

Question 79

In cocker spaniels, black coat color (B) is dominant over red (b), and solid color (S) is dominant over spotted (s).If a red, spotted male is crossed with a black, solid female and all the offspring from several crosses expressed only the dominant traits, the genotype of the female will be

A)BB SS.
B)Bb SS.
C)Bb Ss.
D)BB Ss.
E)none of these.

Question 80

If a woman of blood type A has a child of blood type O, the father may belong to

A)blood type A, AB, or O, but not B.
B)blood type O only.
C)blood type A or B only.
D)blood type A, B, or O, but not AB.
E)any blood type other than A.