Genetics Final Exam Review

The CRISPR-Cas system potentially represents one of the most power techniques in genetics as a result of its role in ________ associated with specific human disorders.
A. Bregulating genes
B. editing genes
C. producing new genes
D. identifying genes

B. editing genes

In the 1600s, William Harvey studied reproduction and development. What is the term given to his theory which states that an organism develops from the fertilized egg by a succession of developmental events that lead to an adult?
A. epigenesis
B. spontaneous generation
C. transduction
D. preformation

A. epigenesis

What is the term given to the theory which put forth the idea that living organisms could arise by incubating nonliving components?
A. evolution
B. spontaneous generation
C. natural selection
D. preformation

B. spontaneous generation

Who, along with Alfred Wallace, formulated the theory of natural selection?
A. Charles Darwin
B. William Harvey
C. Gregor Mendel
D. James Watson

A. Charles Darwin

In many species, there are two representatives of each chromosome. In such species, the characteristic number of chromosomes is called the ________ number. It is usually symbolized
A. diploid; n
B. haploid; 2n
C. haploid; n
D. diploid; 2n

D. diploid; 2n

Which of the following is an example of natural selection?
A. depending on the food a turtle eats, its shell may grow faster or slower
B. bacteria can be effectively killed by treatment with bleach
C. sometime during human's life they break a bone
D. a bird's beak is able to effectively crack the seeds it encounters

D. a bird's beak is able to effectively crack the seeds it encounters

Genetics is defined as the branch of biology associated with ________.
A. mutation and recession
B. replication and recombination
C. transcription and translation
D. heredity and variation

D. heredity and variation

The observable feature of an organism is referred to as a ________.
A. phenotype
B. genotype
C. prototype
D. karyotype

A. phenotype

Which of the following is an example of heredity?
A. Flies and molluscs both have eyes.
B. Both moths and birds have wings and can fly.
C. A man has low blood pressure due to medications.
D. Dalmation dogs all have spots.

D. Dalmation dogs all have spots.

Which is not a component of DNA?
A. nitrogenous base
B. deoxyribose sugar
C. phosphate
D. mRNA

D. mRNA

Genetic information contained in DNA that encodes for an amino acid is referred to as a(n) ________.
A. allele
B. codon
C. trait
D. nucleotide

B. codon

Which of the following processes describes the formation of a complementary RNA molecule?
A. mosaicism
B. translation
C. replication
D. transcription

D. transcription

If a scientist changed a cell's ionic composition and complementarity between DNA strands could no longer occur, what would the scientist first detect?
A. ribosomes would move into the nucleus
B. DNA becomes single stranded
C. DNA strands become shorter
D. RNA would start binding to DNA

B. DNA becomes single stranded

Once a protein is made, its biochemical or structural properties play a role in producing ________.
A. chromosome
B. genotype
C. phenotype
D. DNA

C. phenotype

A primary discovery to generate recombinant DNA molecules was the use of ________.
A. spliceosomes
B. bioinformatics
C. restriction enzymes
D. x-ray diffraction

C. restriction enzymes

The study of the structure, function, and evolution of genes and genomes is referred to as ________.
A. genetics
B. bioinformatics
C. genomics
D. proteomics

C. genomics

________ is a discipline involved in the development of both hardware and software for processing, storing, and retrieving nucleotide and protein data.
A. Genomics
B. Proteomics
C. Recombinant DNA technology
D. Bioinformatics

D. Bioinformatics

Organisms that are well understood from a scientific standpoint and are often used in basic biological research are often called ________.
A. model organisms
B. vectors
C. recombinant DNA technology
D. clones

A. model organisms

Which of the following contains all the others?
A. double helix
B. hydrogen bond
C. nucleotide
D. DNA strand

A. double helix

Who was the Augustinian monk that conducted a decade of experiments on the garden pea, eventually showing that traits are passed from parents to offspring in predictable ways?
A. Francis Crick
B. Gregor Mendel
C. Alfred Wallace
D. Aristotle

B. Gregor Mendel

Living organisms are categorized into two major groups based on the presence or absence of a nucleus. What group is defined by the presence of a nucleus?
A. virus
B. eubacterium
C. eukaryotic organism
D. archaea

C. eukaryotic organism

Organized by the centrioles, what structures are important in the movement of chromosomes during cell division?
A. mitochondria
B. spindle fibers
C. chloroplasts
D. centromeres

B. spindle fibers

Which of the following is not a true statement about mitochondria?
A. the mitochondrial genome is contained in the nucleus
B. the mitochondria transcribe and translate their own genetic information
C. mitochondria are found in plants and animals
D. mitochondria are sites for cellular respiration

A. the mitochondrial genome is contained in the nucleus

The nucleolus organizer region (NOR) is responsible for production of what type of cell structure?
A. ribosome
B. mitochondria
C. endoplasmic reticulum
D. chromatids

A. ribosome

The diploid chromosome number of an organism is usually represented as 2n. Humans have a diploid chromosome number of 46. What would be the expected haploid chromosome number in a human?
A. 92
B. 24
C. 12
D. 23

D. 23

Which of the following terms defines a chromosome in which the centromere is near one end, but not at the end of a chromosome?
A. metacentric
B. acentric
C. telocentric
D. acrocentric

D. acrocentric

Which of the following is incorrect?
A. sex chromosomes are not strictly homologous
B. homologous chromosomes contain identical genetic information
C. a locus is a gene site on a chromosome
D. an allele is an alternate form of the same gene

B. homologous chromosomes contain identical genetic information

During interphase of the cell cycle, ________.
A. cytokinesis occurs
B. DNA content essentially doubles
C. the nuclear membrane disappears
D. sister chromatids move to opposite poles

B. DNA content essentially doubles

What significant genetic function occurs in the S phase of the cell cycle?
A. cytokinesis
B. centromere division
C. DNA synthesis
D. chromosome condensation

C. DNA synthesis

Which of the following represents the correct sequence of events in mitosis?
A. telophase-prophase-prometaphase-metaphase-anaphase
B. prophase-prometaphase-metaphase-anaphase-telophase
C. prometaphase-prophase-metaphase-anaphase-telophase
D. prophase-metaphase-prometaphase-anaphase-telophase

B. prophase-prometaphase-metaphase-anaphase-telophase

Migration of chromosomes is made possible by the binding of the spindle to the ________.
A. centrosome
B. centriole
C. kinetochore
D. equatorial plate

C. kinetochore

The event referred to as disjunction occurs during ________.
A. metaphase
B. telophase
C. prophase
D. anaphase

D. anaphase

At which stage of cell division do sister chromatids go to opposite poles?
A. mitotic anaphase and anaphase of meiosis II
B. mitotic anaphase only
C. mitotic anaphase and anaphase of meiosis I
D. anaphase of meiosis I only

A. mitotic anaphase and anaphase of meiosis II

During meiosis, chromosome number reduction takes place in ________.
A. anaphase I
B. prophase I
C. metaphase I
D. anaphase II

A. anaphase I

A bivalent at prophase I contains ________ chromatids.
A. four
B. two
C. one
D. three

A. four

In an organism with 52 chromosomes, how many chromatids would be expected in each cell after the second meiotic division?
A. 26
B. 52
C. 13
D. 104

A. 26

The meiotic cell cycle involves ________ number of cell division(s) and ________ number of DNA replication(s).
A. two; zero
B. one; two
C. two; one
D. one; one

C. two; one

If a typical somatic cell has 64 chromosomes, how many chromosomes are expected in each gamete of that organism?
A. 64
B. 128
C. 32
D. 16

C. 32

Which of the following is true about the second meiotic division?
A. The products are four identical gametes.
B. Synapsis occurs in the second meiotic division.
C. Sister chromatids disjoin and are pulled to opposite poles.
D. Nondisjunction would lead to extra bivalents forming.

C. Sister chromatids disjoin and are pulled to opposite poles.

Which of the following is not a source of genetic variation in meiosis?
A. law of independent assortment
B. the random lining up of chromosomes on the metaphase plate
C. crossing over
D. polar body formation

D. polar body formation

Mendel utilized the garden pea, Pisum sativumfor his studies based on features that include all but ________.
A. easy to grow
B. has visible features with a wide spectrum of intermediates
C. can generate a large number of progeny
D. reaches maturity in a single season

B. has visible features with a wide spectrum of intermediates

The physical expression of a trait is referred to as a(n) ________.
A. gene
B. phenotype
C. allele
D. genotype

B. phenotype

The process that leads to the development of haploid gametes is best described as ________.
A. replication
B. segregation
C. independent assortment
D. Mendelian inheritance

B. segregation

Assuming a typical monohybrid cross in which one allele is completely dominant to the other, what phenotypic ratio is expected if the F1s are crossed?
A. 3:1
B. 1:1
C. 3:2
D. 2:1

A. 3:1

Mendel crossed two pea plants with round seeds. All seeds of the offspring were round. He then crossed a plant with round seeds to a plant with wrinkled seeds and all offspring had wrinkled seeds. Which of the following is true?
A. the plants he used were not true breeding
B. a mutation occurred
C. round is dominant
D. wrinkled is dominant

D. wrinkled is dominant

If an F2 generation from a F1 self-cross always yields offspring in a 3:1 phenotypic ratio, which of the following P crosses could have occurred?
A. AA × AA
B. aa × Aa
C. AA × aa
D. Aa × AA

C. AA × aa

A cross between two individuals with different phenotypes that resulted in approximately 50% of each type of offspring would indicate the cross was ________.
A. a heterozygous dominant crossed to a heterozygous recessive
B. true breeding dominant to recessive
C. a homozygous recessive crossed to a heterozygous recessive
D. a heterozygous dominant crossed to a homozygous recessive

D. a heterozygous dominant crossed to a homozygous recessive

Mendel indicated that traits were made up of unit factors. Today, we call unit factors ________.
A. genotypes
B. genes
C. alleles
D. characters

C. alleles

A recessive allele in dogs causes white spots. If two solid colored dogs are mated and produce a spotted offspring, what is the percentage chance their next puppy would be solid colored?
A. about 90%
B. 25%
C. 75%
D. 50%

C. 75%

Polydactyly is expressed when an individual has extra fingers and/or toes, and is transmitted via an autosomal dominant allele. Assume that a man with six fingers on each hand and six toes on each foot marries a woman with a normal number of digits. The couple has a son with normal hands and feet, but the couple's second child has extra digits. What is the probability that their next child will have polydactyly?
A. 1/8
B. 3/4
C. 7/16
D. 1/2

D. 1/2

Tightly curled or wooly hair is caused by a dominant gene in humans. If a heterozygous curly-haired person marries a person with straight hair, what percentage of their offspring would be expected to have straight hair?
A. 50%
B. 25%
C. 0%
D. 75%

A. 50%

Albinism, lack of pigmentation in humans, results from an autosomal recessive gene. Two parents with normal pigmentation have an albino child. What is the probability that their next two children will be albino?
A. 3/4
B. 1/3
C. 1/2
D. 1/16

D. 1/16

The autosomal (not X-linked) gene for brachydactyly, short fingers, is dominant to normal finger length. Assume that a female with brachydactyly in the heterozygous condition is married to a man with normal fingers. What is the probability that their first child will have brachydactyly?
A. 1/2
B. 3/4
C. 1/4
D. 1/8

A. 1/2

A certain type of congenital deafness in humans is caused by a rare autosomal dominant gene. In a mating involving a deaf man and a deaf woman, could all the children have normal hearing?
A. Yes, assuming that the parents are heterozygotes (because the gene is rare), it is possible that all of the children could have normal hearing.
B. No, because it is dominant. Children always get the dominant alleles.
C. No, because children favor their parents.
D. Yes, because traits assort independently.

A. Yes, assuming that the parents are heterozygotes (because the gene is rare), it is possible that all of the children could have normal hearing.

Which of the following describes the product law?
A. The probability of two or more independent events occurring simultaneously is equal to the sum of their individual probabilities.
B. The probability of two or more independent events occurring simultaneously is equal to the product of their individual probabilities.
C. The probably of two linked events occurring simultaneously is equal to the probabilities of each individual event.
D. The product of the sum of the probabilities of two simultaneous events describes the ability of those two events to occur together.

B. The probability of two or more independent events occurring simultaneously is equal to the product of their individual probabilities.

Which phenotypic ratio is likely to occur in crosses of two completely dominant, independently segregating gene pairs when both parents are fully heterozygous?
A. 1:1:1:1
B. 9:3:3:1
C. 2:4:6:8
D. 3:2:3:1

B. 9:3:3:1

What is segregation?
A. Chromosomes can swap information during meiosis.
B. Fertilization is random.
C. During gamete formation, segregating pairs of unit factors assort independently of each other.
D. During gamete formation, allele pairs are separated to form haploid gametes.

D. During gamete formation, allele pairs are separated to form haploid gametes.

What conditions are likely to apply if the progeny from the cross AaBb× AaBb appear in the 9:3:3:1 ratio?
A. gene interaction and independent assortment
B. dihybrid cross with incomplete dominance
C. complete dominance, independent assortment, and no gene interaction
D. incomplete segregation and complete dominance

C. complete dominance, independent assortment, and no gene interaction

How many different possible gametes can be obtained from an organism with the following genotype AaBbCc?
A. 16
B. 9
C. 8
D. 4

C. 8

Assuming independent assortment, what proportion of the offspring of the cross AaBbCcDd × AabbCCddwill have the aabbccdd genotype?
A. 1/512
B. 1/256
C. 1/64
D. 0

D. 0

A mutation in a gene that results in a loss of a functional product of that gene best defines what type of mutation?
A. multiple allelism
B. null
C. incomplete dominance
D. gain of function

B. null

Gain-of-function mutations are associated with being ________.
A. neutral
B. wild type
C. dominant
D. recessive

C. dominant

If the wrinkled-wing mutation in Drosophilais dominant and designated Wr, a fruit fly with the genotype Wr+ Wr+ would exhibit what phenotype?
A. partially wrinkled wings
B. one wrinkled wing and one normal wing
C. wrinkled wings
D. wild-type wings

D. wild-type wings

With incomplete dominance, a likely ratio resulting from a monohybrid cross would be ________.
A. 3:1
B. 1:2:1
C. 1:2:2:4
D. 9:3:3:1

B. 1:2:1

The MN blood group is a codominant trait as a result of which of the following?
A. presence of M, M/N intermediate, and N cell surface glycoproteins on blood cells
B. presence of M cell surface glycoproteins on some blood cells and N glycoproteins on others
C. presence of a M/N intermediate cell surface glycoprotein on blood cells
D. presence of both M and N cell surface glycoproteins on the same blood cell

D. presence of both M and N cell surface glycoproteins on the same blood cell

What is the probability of having a child with the N blood type, if both parents are MN?
A. 1/4
B. 1/2
C. 0
D. 3/4

A. 1/4

Which of the following is not a characteristic of the ABO gene locus?
A. multiple alleles
B. four possible phenotypes
C. epistasis
D. codominance

C. epistasis

The presence of more than two alternative forms of a given gene would be called ________.
A. alternation of generations
B. multiple alleles
C. codominance
D. hemizygosity

B. multiple alleles

A couple each with blood type AB and normal pigmentation have a child with AB blood type and albinism. What is the probability that their next child will have the same phenotype as the first child?
A. 1/8
B. 1/4
C. 9/16
D. 3/16

A. 1/8

A couple in which one parent is blood type A and the other is blood type B, and both have normal pigmentation, have a child that is blood type O and has albinism. What is the probability that their next child will have normal pigmentation and blood type A?
A. 1/8
B. 9/16
C. 3/16
D. 1/16

C. 3/16

A condition in which one gene pair masks the expression of a nonallelic gene pair is called ________.
A. epistasis
B. codominance
C. additive alleles
D. recessiveness

A. epistasis

In the mouse, gene B can produce black pigment from a colorless precursor molecule. A mouse having at least one B allele can produce black pigment, whereas the homozygous recessive mouse (bb) cannot and is albino. The agouti locus (A) can convert the black pigment to brown in the presence of at least one dominant A allele, whereas the homozygous recessive (aa) cannot convert the black pigment to brown. What would be the probability of an albino mouse offspring if the parents were genotypes AaBb and AAbb?
A. 1/2
B. 1/4
C. 1/16
D. 3/16

A. 1/2

Individuals from two separate true-breeding strains of white deer mice are crossed yielding all grey offspring. White is recessive to gray color based on crossing mice from each strain with a grey mouse. Which of the following would best explain this result?
A. multiple alleles
B. lethal alleles
C. epistasis
D. complementation

D. complementation

The phenomenon of a gene which has multiple phenotypic effects on an individual is referred to as ________.
A. expressivity
B. penetrance
C. continuous variation
D. pleiotropy

D. pleiotropy

With which of the following would hemizygosity most likely be associated?
A. incomplete dominance
B. sex-limited inheritance
C. X-linked inheritance
D. autosomal dominance

C. X-linked inheritance

Because of the mechanism of sex determination, males of many species can be neither homozygous nor heterozygous. Such males are said to be ________.
A. complementary
B. recessive
C. hemizygous
D. dominant

C. hemizygous

The white-eye gene in Drosophilais recessive and sex-linked. Assume that a white-eyed female is mated to a wild-type male. What would be the phenotypes of the offspring?
A. 1/2 wild-type females, 1/4 wild-type males, 1/4 white-eyed males
B. 1/2 wild-type females, 1/2 white-eyed males
C. 1/2 wild-type males, 1/4 wild-type females, 1/4 white-eyed females
D. 1/4 wild-type females, 1/4 white-eyed females, 1/4 wild-type males, 1/4 white-eyed males

B. 1/2 wild-type females, 1/2 white-eyed males

Which of the following statements would be the most likely scenario of offspring of a woman exhibiting an X-linked recessive disorder and a man that does not exhibit the trait?
A. all daughters will not have the disorder and all sons will have the disorder
B. all offspring with have the disorder
C. half the daughters and half the sons will have the disorder
D. all daughters will not have the disorder and half the sons will have the disorder

A. all daughters will not have the disorder and all sons will have the disorder

A deficiency of the enzyme glucose-6-phosphate dehydrogenase (G6PD) is inherited as an X-linked recessive trait in humans. A phenotypically normal woman (whose father had G6PD) is married to a man with normal G6PD function. What fraction of their sons would be expected to have G6PD deficiency?
A. 0
B. 1/4
C. 1/2
D. all

C. 1/2

A trait exhibited in one sex but not the other is referred to as ________.
A. sex-limited
B. sex-linked
C. sex-inluenced
D. genomic imprinting

A. sex-limited

The Protenor mode of sex determination is the ________.
A. scheme based on F plasmids inserted into the FMR-1 gene
B. XO/YY scheme
C. hermaphroditic scheme
D. XX/XO scheme

D. XX/XO scheme

The Lygaeus mode of sex determination is the ________.
A. XO/YY scheme
B. XX/XO scheme
C. XY/XX scheme
D. scheme based on single translocations in the X chromosome

C. XY/XX scheme

In humans, the genetic basis for determining the sex "male" is accomplished by the presence of ________.
A. high levels of estrogen
B. a portion of the Y chromosome
C. one X chromosome
D. a balance between the number of X chromosomes and the number of haploid sets of autosomes

B. a portion of the Y chromosome

Klinefelter syndrome in humans, which leads to underdeveloped testes and sterility, is caused by which chromosomal condition?
A. 47, XXY
B. 47, 21+
C. 47, XYY
D. 45, X

A. 47, XXY

Which of the following elements is responsible for determining male sex in humans?
A. PARS
B. Xist
C. SRY
D. Xic

C. SRY

Which of the following elements allows for homologous pairing in meiosis?
A. Xic
B. PARS
C. SRY
D. MSY

B. PARS

Which of the following is not part of the Y chromosome in humans?
A. Both Xic and Xist
B. Xic
C. MSY
D. Xist

A. Both Xic and Xist

The sex of birds, some insects, and other organisms is determined by a ZWchromosomal arrangement in which the males have like sex chromosomes (ZZ) and females are ZW (similar to XYin humans). Assume that a recessive lethal allele on the Zchromosome causes death of an embryo in birds. What sex ratio would result in the offspring if a cross were made between a male heterozygous for the lethal allele and a normal female?
A. 4:1 male to female
B. 2:1 male to female
C. 1:1 male to female
D. 3:1 male to female

B. 2:1 male to female

If a population of humans carries an X-linked lethal recessive allele that causes spontaneous abortions in the first trimester, how would you expect this to affect the sex ratio of that population?
A. There would be a reduced number of males
B. It would be 1:1 male to female ratio.
C. There would be a reduced number of females.
D. There would be more intersex individuals.

A. There would be a reduced number of males

For an individual with the XXY chromosomal composition, the expected number of Barr bodies in interphase cells is ________.
A. three
B. one
C. zero
D. two

B. one

Which of the following has one Barr body?
A. Klinefelter's
B. Klinefelter's and normal female
C. Triplo-X female
D. Turner's

B. Klinefelter's and normal female

Which of the following elements represents a large untranslated transcript involved in inactivation?
A. Xic
B. Xist
C. SRY
D. MSY

B. Xist

In Drosophila, sex is determined by a balance between the number of haploid sets of autosomes and the number of ________.
A. chromomeres
B. X chromosomes
C. Y chromosomes
D. centromeres

B. X chromosomes

Assume that you are told that a particular organism, Drosophila, has the XO chromosome complement. You are also told that the autosomal complement is a normal 2n. You know that in humans the XO complement is female determining. What would be the sex of this fly and why?
A. This fly would be female due to no Y chromosome.
B. This fly would be male due to an X:A ratio of 1/2.
C. This fly would be considered intersex based on it's X:A ratio.
D. This fly would be a female due to the presence of the X.

B. This fly would be male due to an X:A ratio of 1/2.

Which gene is dependent on the X:A ratio for it's function in sex determination in Drosophila?
A. dsx
B. sxl
C. SRY
D. tra

B. sxl

Which protein is responsible for converting androgens into estrogens?
A. aromatase
B. testis determining factor
C. transformer
D. sex lethal

A. aromatase

Imagine you discover an unknown species of reptile that has a male to female ratio that is very low in cool climates. As seasonal temperatures warm you notice that the male to female ratio increases. What mode of sex determination appears to be involved?
A. Class I temperature dependence
B. Protenor mode
C. Class II temperature dependence
D. Lygaeus mode

A. Class I temperature dependence

Imagine you discover an unknown species of reptile and study its sex ratio. You observe that when climate temperatures are cool the male to female ratio is very low. As the climate warms up the male to female ratio raises and then goes back down under hot temperatures. Hat mode of sex determination appears to be involved?
A. Class III temperature dependence
B. Class I temperature dependence
C. Class II temperature dependence
D. Lygaeus mode

A. Class III temperature dependence

If a reptile had a null mutation in the aromatase gene what would be the predicted outcome?
A. Mostly Metamales.
B. 1:1 male to female sex ratio.
C. More intersex individuals.
D. Males even in female producing temperatures.

D. Males even in female producing temperatures.

A fruit fly with a chromosome formulation of 2X:3A would be which of the following?
A. female
B. male
C. metamale
D. intersex

D. intersex