Deck 12: Patterns of Inheritance

Question 1

Which of the following choices represents the genotype of an individual diploid organism?

A)BbCCdd
B)BCd
C)bCd
D)BbCd

Answer 1

A

Question 2

A mutation that occurs in a diploid cell can be inherited only if the

A)mutated allele is recessive.
B)mutated allele is dominant.
C)mutation occurs in a cell that produces gametes.
D)same mutation also occurs on the homologous chromosome.

Answer 2

C

Question 3

Which of the following observations refutes the theory of blending inheritance?

A)When a red plant is crossed with a white plant, the resulting offspring are pink.
B)Most of the features of offspring are not intermediates of their parents' traits.
C)Gametes carrying different types of alleles cannot fuse successfully.
D)After meiosis, two copies of a given gene end up in the same gamete.

Answer 3

B

Question 4

The black arrow in the image below indicates the biological unit of inheritance. These structures contain a(n)

A)protein molecule surrounded by many DNA molecules.
B)RNA molecule surrounded by phospholipids.
C)RNA molecule that forms a complex with many packaging proteins.
D)DNA molecule that forms a complex with many packaging proteins.

Question 5

The chance of a parent's passing on a given allele to a child _____ each time he or she has another child.

A)is reduced
B)is increased
C)is the same
D)changes

Question 6

The figure below shows three generations in one of Mendel's experiments and demonstrates that purple flower color is dominant over white flower color in peas. Which of the following is the best rationale for this conclusion?

A)In the F2 generation, more plants have purple flowers. In any cross, the allele that is most common in the offspring is dominant.
B)Members of the F1 generation are heterozygous. Whatever allele is visible in a known heterozygote is considered dominant.
C)The stronger, or in this case, darker, allele is always considered dominant.
D)An individual that produces more offspring gives more alleles to the next generation. As a result, that allele dominates the next generation.

Question 7

A recessive allele can only appear in the phenotype of an individual

A)in the F1 generation.
B)exposed to certain environmental conditions.
C)who carries the mutation in his or her gametes.
D)who is homozygous for the mutation.

Question 8

Which of the following statements is not true?

A)Two organisms with the same genotype are homozygous.
B)Two organisms with the same phenotype may have different genotypes.
C)A heterozygous organism may have the same phenotype as a homozygous organism.
D)A heterozygous organism has the same number of copies of a given gene as a homozygous organism.

Question 9

If a person has one copy of each of two different alleles for a given gene, the person is _____ for that trait.

A)heterozygous
B)homozygous
C)recessive
D)true-breeding

Question 10

A thoroughbred racehorse could have at most _____ alleles of the same gene.

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

Question 11

A tall plant mates with itself and produces all tall offspring. This cross is repeated for many generations with the same results. The parental plant is most likely

A)heterozygous.
B)completely dominant.
C)mutated.
D)true-breeding.

Question 12

Which of the following symbols correctly represents a person who has a homozygous genotype?

A)Ww
B)WW
C)XY
D)Wx

Question 13

Is it possible for two organisms with the same genotype to have different phenotypes?

A)No; identical genotypes lead to identical phenotypes.
B)No; the DNA of the recessive alleles not expressed in the phenotype is degraded within each cell.
C)Yes; the expression of the genotype can be affected by the environment.
D)Yes; the phenotype expressed determines what the genotype will be.

Question 14

An allele is

A)a version of a gene.
B)a trait that can be affected by the external environment.
C)always codominant to its counterpart in another chromosome.
D)the result of a change in phenotype.

Question 15

Which of the following statements is true?

A)Specific mutations occur because they are needed.
B)Mutations only occur during development.
C)All mutations are harmful.
D)Gametes fuse without regard to which mutations they carry.

Question 16

The individuals Mendel observed in the F₁ generations were always

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

Question 17

Which of the following pairs of words can be used correctly to describe alleles?

A)dominant or recessive
B)homozygous or heterozygous
C)genotype and phenotype
D)codependent and mutation

Question 18

The figure below shows three generations in one of Mendel's experiments. According to the data in this figure, Mendel's F₂ generation contains many more purple flowers than white flowers. Which of the following is the best explanation of this observation?

A)Three-quarters of the offspring must receive the white allele.
B)The chance of an individual offspring receiving a white allele is only 25 percent.
C)The probability of any individual offspring receiving a copy of the purple allele is 3:1.
D)The white allele is only dominant in about 25 percent of the offspring that inherit it.

Question 19

Mendel's laws were able to predict accurately the pattern of inheritance for situations in which

A)alleles are affected by their environment.
B)one allele completely masks another allele.
C)alleles of one gene alter the effect of a different gene.
D)a given character is determined by more than one gene.

Question 20

Most genes contain instructions for building

A)carbohydrates.
B)steroids.
C)proteins.
D)lipids.

Question 21

What is the smallest number of traits that are needed to test Mendel's law of independent assortment?

A)one
B)two
C)four
D)eight

Question 22

Cystic fibrosis is caused by a recessive gene. If C = normal and c = cystic fibrosis, how can a child with cystic fibrosis have two parents who do not have cystic fibrosis?

A)The child has a genotype of CC.
B)The parents have genotypes of CC and Cc.
C)The parents have genotypes of Cc and Cc.
D)The child has a genotype of Cc.

Question 23

Humans have many genes that contribute to the unique array of proteins found on their red blood cells. Your MN blood type (the letters indicate the presence of M and N proteins on the red blood cells)is determined by the codominant alleles Lᴹ and Lᴺ. Which of the following genotypes could be produced when a man with MN blood and a woman with MN blood mate?

A)LMLM
B)LMLN
C)LNLN
D)all of the above

Question 24

The best way to get accurate results from a probability exercise is to

A)choose an example with incomplete dominance.
B)know the answer in advance.
C)choose an example that will come out 50-50.
D)make a large number of observations.

Question 25

Feather color in a certain species of bird is controlled by a pair of alleles that exhibit incomplete dominance. If birds that are homozygous for one allele are black and birds that are homozygous for the other allele are white, then heterozygous birds would be

A)black.
B)white.
C)gray.
D)black with white stripes.

Question 26

When two individuals who are heterozygous for a gene are mated, we would predict a _____ ratio of dominant to recessive phenotype in the offspring.

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

Question 27

The leaf color of a certain plant is controlled by one gene. For that gene, the allele G = orange and g = green. You have a plant with orange leaves, but do not know whether that plant's genotype is GG or Gg. Which of the following would help you determine the plant's genotype?

A)Cross the plant to another plant with orange leaves.
B)Cross the plant to a plant with green leaves.
C)Cross two true-breeding, orange-leaved plants to each other and then cross one of their offspring to the plant with the unknown genotype.
D)Change the environment in which the plant grows to find the conditions that cause the leaves to produce the orange color.

Question 28

An individual with the genotype Aa mates with an individual with the genotype AA. Which of the following is true?

A)These two individuals will have four offspring.
B)Half of the offspring will be Aa.
C)Twenty-five percent of the offspring will be aa.
D)both a and b

Question 29

In the cross depicted below, two parent plants, one with red flowers and the other with white flowers produce pink offspring. The white and red alleles for flower color in this plant exhibit

A)homozygosity.
B)codominance.
C)pleiotrophy.
D)incomplete dominance.

Question 30

In the Punnett square shown below, the lettered circles on the top and left of the square (indicated by the arrows)represent the

A)offspring that will be produced by the cross.
B)genotypes of the parents involved in the cross.
C)gametes that may be produced by each parent involved in the cross.
D)offspring that could be produced by the cross.

Question 31

Which of the following represents all of the possible gametes that can be formed by an individual with the genetic makeup FfGgHH?

A)FGH, FgH, fGH, fgH
B)Ff, Gg, HH
C)FG, FH, Fg, fH, fG, fg, GH, gH
D)FfGhHH, FFGGHH, ffgghh

Question 32

Which of the following expresses Mendel's law of segregation?

A)All dominant alleles of different genes divide into different cells from the recessive alleles.
B)Two copies of a gene separate during meiosis and end up in different gametes.
C)When gametes form, the genes originally from one parent all end up in different gametes from the genes originally from the other parent.
D)Gametes with recessive alleles will fuse only with each other.

Question 33

Suppose D were dominant and d were recessive, and you could label the D allele in the P generation with a radioactive substance that could be inherited over several generations. You create hybrids by mating your radioactive DD individuals to dd individuals. Finally, you cross two Dd individuals. In 1,000 offspring, how many would you predict would be radioactive?

A)250
B)500
C)750
D)1,000

Question 34

If the D allele is completely dominant over the d allele, what percentage of the offspring will have the dominant phenotype when two heterozygous individuals mate?

A)25 percent
B)50 percent
C)75 percent
D)100 percent

Question 35

Inheritance of ABO blood type in humans is an example of

A)codominance.
B)complete dominance of one allele over another.
C)a gene that is coded by more than two alleles.
D)all of the above

Question 36

Which of the following statements is a basic summary of one of Mendel's laws?

A)All beneficial human genetic traits are dominant, and harmful traits are recessive.
B)The pattern of inherited characteristics of organisms is not predictable.
C)The separation of alleles for one gene does not affect the separation of alleles for other genes.
D)Recessive alleles cause the death of the gamete.

Question 37

In a genetic cross of Gg with Gg guinea pigs, none of the four offspring were gg. This

A)disproves Mendel's law of independent assortment.
B)neither supports nor disproves Mendel's law of independent assortment.
C)supports Mendel's law of independent assortment.
D)supports Mendel's law of segregation.

Question 38

A Punnett square is used to

A)determine the source of new alleles.
B)determine how many genes control a given trait.
C)predict the gametes that will be produced by an organism.
D)predict the outcome of a genetic cross.

Question 39

This figure depicts red blood cells from a mother, a father, and their child. The mother and father are the biological parents of the child.
What is the mother's genotype for ABO blood type?

A)IAIA
B)IAIB
C)IAi
D)not enough information provided

Question 40

Which of the following statements is true?

A)Mendel's laws are less accurate than Punnett square results.
B)Mendel's laws are useful only in unusual situations.
C)Mendel's laws correctly explain how genes are inherited.
D)Mendel's laws correctly predict the phenotype of an organism.

Question 41

Gregor Mendel deduced the laws of ____________________ by observing the offspring in a series of pea-breeding experiments.

Question 42

One of the first medical tests a newborn receives determines if the child has phenylketonuria (PKU). PKU is the result of a mutation in a single gene that causes mental retardation and a host of other phenotypes (light hair and skin color, eczema, and a "mousy" smell). By detecting PKU early, doctors are able to reduce the effect of this condition with a modified diet. PKU is an example of

A)epistasis.
B)a polygenic trait.
C)pleiotrophy.
D)codominance.

Question 43

When a ____________________ variety of a plant is self-fertilized, all of its offspring have the same phenotype as the parent.

Question 44

If two alleles for the same trait have an equal effect on the phenotype, the alleles are ____________________.

Question 45

The observable physical characteristics of an organism are known as its ____________________.

Question 46

The first generation of phenotypes resulting from a genetic cross between two members of the parental generation would be seen in the ____________________ generation.

Question 47

The Iᴬ and Iᴮ alleles involved in human blood type differ in that they attach different ____________________ to the surface of red blood cells.

Question 48

If an offspring has a total of 32 genes, it inherited ____________________ genes from each parent.

Question 49

The lettered fragment indicated by the black arrow in the image below is the part of a chromosome responsible for producing ____________________ that ultimately determine the phenotypes of an individual.

Question 50

____________________ dominance is expressed in a genetic cross in which the heterozygous phenotype is intermediate between the two homozygous phenotypes.

Question 51

The genetic makeup of an organism, such as Gg, is its ____________________.

Question 52

If an offspring has a total of 32 alleles for 16 genes, it inherited ____________________ alleles from each parent.

Question 53

Two genes control fur color in Labrador retrievers. The first gene determines whether the pigment to be deposited in the hairs will be black or brown. The second gene determines whether the pigments are put into the dog's hairs at all. A dog homozygous for the recessive allele of this second gene will be yellow because no pigment is deposited in its hairs. This is an example of

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

Question 54

Alternate versions of the same gene, such as blue or brown for eye color, are known as ____________________.

Question 55

A genetic ____________________ is a controlled mating experiment used to examine the inheritance of a particular gene.

Question 56

During meiosis, two copies of a gene separate and end up in different ____________________.

Question 57

Mendel's manuscript discussing his pea-breeding results is considered one of the two most important scientific papers of the nineteenth century because he was the first to explain how

A)mutations produced the variety of alleles displayed by individuals of the same species.
B)traits are passed from one generation to the next.
C)meiosis controls the distribution of alleles to each gamete.
D)genes are arranged on chromosomes in the cell.

Question 58

We need a hammer to pound nails into a board. Even if we have the nails, we cannot pound them without first getting hold of a hammer. This is similar to the genetic relationship known as

A)heterozygosity.
B)codominance.
C)epistasis.
D)independent assortment.

Question 59

Most human genetic characters are

A)controlled by one gene.
B)not inherited according to Mendel's laws.
C)controlled by more than one gene.
D)not heritable.

Question 60

According to Mendel's law of ____________________, when gametes are formed, the separation of alleles for one gene is unrelated to the separation of alleles for other genes.

Question 61

A genetic cross is used to produce organisms from species that would not normally interbreed.

Question 62

Chromosomes are located on genes.

Question 63

New alleles arise as a result of independent assortment during meiosis.

Question 64

Environmental factors can alter the effects of genes.

Question 65

Mendel's hypotheses regarding inheritance in peas were generally accepted when he published them in 1865.

Question 66

Temperature can affect phenotype.

Question 67

The individuals in the image below exhibit a variety of physical, biochemical, and behavioral characteristics that are based on their DNA sequences.

Question 68

In this Punnett square, the genotypes inside the boxes (a few are indicated by arrows here)represent the number and type of offspring a given pair of individuals will produce when mated.

Question 69

The plant shown in the image below would be considered a hybrid.

Question 70

There are no known exceptions to Mendel's law of independent assortment.

Question 71

If both copies of a given gene in an organism are identical, the organism is homozygous for that trait.

Question 72

Most traits are under the control of more than one gene.

Question 73

A genotype is always expressed in the phenotype.

Question 74

Traits that are determined by the effect of more than one gene are known as polygenic.

Question 75

Experiments involving small numbers of offspring give more reliable results than experiments observing large numbers of offspring.