FINAL EXAM ? Flashcards
The building blocks of DNA are
A. amino acids
B. nucleotides
C. carbohydrates
D. lipids
E. enzymes
B. nucleotides
A variation of a gene is called a(n)
A) allele
B) morph
C) genome
D) proteome
E) species
A) allele
A characteristic that an organism displays is called __________.
A) trait
B) gene
C) chromosome
D) gene expression
E) DNA
A) trait
During sexual reproduction, each parent contributes one set of chromosomes. Similar chromosomes from each parent are called __________.
A) sex chromosomes
B) sister chromatids
C) homologs
D) karyotypes
C) homologs
In animals, somatic cells are ________ and gametes are __________.
A) haploid; haploid
B) diploid; haploid
C) haploid; diploid
D) diploid; diploid
B) diploid; haploid
The end result of meiosis in animals is ______.
a. four diploid cells
b. four haploid cells
c. two haploid cells
d. two diploid cells
b. four haploid cells
A diploid cell within an organism’s body that is not a reproductive cell is _______.
A) rare
B) an allele
C) a somatic cell
D) a gamete
E) a sperm cell
C) a somatic cell
Which of the following would contain genetic material that is 100% identical?
A) homologous chromosomes
B) sister chromatids
C) X and Y chromosomes
D) All of these choices are identical.
B) sister chromatids
An individual who has two different alleles for a trait is called ____________.
A) isozygous
B) true-breeding
C) homozygous
D) haploid
E) heterozygous
E) heterozygous
A true-breeding line of green pod pea plants is crossed with a true-breeding line of yellow pod plants. All of their offspring have green pods. From this information, it can be stated that the green color is _____ to the yellow color.
A) dominant
B) recessive
C) blended
D) subservient
E) None of these choices are correct.
A) dominant
The differences in inherited traits among individuals in a population are called _______.
A. genetic variation
B. homozygous
C. heterozygous
D. natural selection
A. genetic variation
When Mendel crossed two plants that were heterozygous for a single trait, what was the phenotypic ratio of their offspring?
A) 3:1
B) Varied depending on the trait
C) 1:2:1
D) 7:4
E) 9:3:3:1
A) 3:1
When Mendel crossed two plants that were heterozygous for a single trait, what was the genotypic ratio of their offspring?
A) 1:2:1
B) 3:1
C) 9:3:3:1
D) Varied depending on the trait
E) 1:1
A) 1:2:1
In a two-factor cross using Mendelian inheritance, if both parents are heterozygous for both traits, what will be the phenotypic ratio of their offspring?
A. 1:2:1
B. 9:3:3:1
C. 1:1
D. 3:1
E. Varied depending on the trait
B. 9:3:3:1
Mendel’s work with two-factor crosses led directly to which of the following?
A) chromosomal theory of inheritance
B) theory of biological evolution
C) law of independent assortment
D) particulate theory of inheritance
E) law of segregation
C) law of independent assortment
Which situation below would violate the law of independent assortment, as understood by Mendel?
A. Combining certain alleles of different genes results in a plant that grows poorly.
B. A mutant gene can prevent pod formation altogether, thus preventing expression of the round or wrinkled pea alleles.
C. A plant breeder is able to create a true-breeding line that combines the alleles for white flowers and wrinkled peas.
D. A gene for petal color does not affect the expression of a gene for petal number.
E. A gene for leaf shape is linked to a gene for petal number nearby on the same chromosome, so their alleles usually segregate together.
A gene for leaf shape is linked to a gene for petal number nearby on the same chromosome, so their alleles usually segregate together.
Dosage compensation offsets the problem associated with differences in the number of ________ chromosomes in many species.
A. autosome
B. somatic
C. sex
D. nuclear
C. sex
How many Barr bodies would an individual with a XXY genotype possess?
A. 1
B. 2
C. 0
A. 1
In a Z-W system, which is considered to be the homogametic sex?
A) males
B) females
A) males
During sexual reproduction, gametes are made that contain ______ amount of genetic material as a somatic cell in the organism.
A) the same
B) twice the
C) half the
D) A quarter of the
C) half the
Polydactyly in humans is an example of __________.
A. incomplete dominance
B. gene dosage
C. incomplete penetrance
D. sex-limited inheritance
E. codominance
C. incomplete penetrance
A heterozygote possesses a phenotype that is intermediate between the homozygous dominant and homozygous recessive phenotypes. This is most likely an example of ________.
A. sex-influenced inheritance
B. incomplete dominance
C. lethal alleles
D. gene dosage
B. incomplete dominance
In human blood groups, the fact that an individual can have an AB blood type is an example of ___________.
A) incomplete penetrance
B) temperature-sensitive conditional allele
C) codominance
D) sex-influenced trait
E) incomplete dominance
C) codominance
In overdominance, the _______ genotype is beneficial over the _______ genotypes.
A. homozygous recessive; homozygous dominant
B. heterozygous; homozygous
C. homozygous; heterozygous
D. homozygous dominant; homozygous recessive
E. incomplete dominant; codominant
B. heterozygous; homozygous
For a certain trait, a heterozygous individual has a selective advantage over a homozygous dominant or homozygous recessive individual. This is called ________.
A.codominance
B.incomplete dominance
C.multiple allele systems
D.overdominance
E.incomplete penetrance
D.overdominance
Genes that are not required for survival, but are likely to be beneficial to the organism, are called _________.
A. lethal alleles
B. conditional lethal alleles
C. essential genes
D. nonessential genes
E. semilethal alleles
D. nonessential genes
The alleles that cause Huntington disease in humans are an example of ____________.
A) essential genes
B) nonessential genes
C) semilethal alleles
D) lethal alleles
E) sex linked allele
D) lethal alleles
The symbiotic relationship where one organism lives inside another species is called
A. heteroplasmy.
B. cytoplasmic inheritance.
C. endosymbiosis.
D. exosymbiosis.
E. genomic imprinting.
C. endosymbiosis.
Which of the following is primarily responsible for the maternal effect?
A) nurse cells
B) oocytes
C) sperm cells
D) placenta
A) nurse cells
G and g are dominant and recessive alleles, respectively, for a gene. If a mating of a gg female with a Gg male resulted in offspring that all have the recessive phenotype, this would most likely be an example of
A. a recessive lethal gene.
B. a maternal effect gene.
C. imprinting which results in silencing of the maternal alleles.
D. environmental influence on phenotype.
B. a maternal effect gene.
In maternal effect, the _____ of the mother determines the _______ of the offspring.
A) phenotype, genotype
B) genotype, phenotype
C) rRNA, tRNA
D) imprinting, genotype
B) genotype, phenotype
What controls the coiling of shells in snail offspring?
A) father’s phenotype
B) mother’s genotype
C) mother’s phenotype
D) father’s genotype
C) mother’s phenotype
In genomic imprinting, erasure of DNA methylation occurs in the
A) chloroplasts.
B) cells destined to become gametes.
C) mitochondria.
D) somatic cells of the embryo.
B) cells destined to become gametes.
What is the molecular mechanism for imprinting a gene?
A. methylation
B. nitration
C. phosphorylation
D. acetylation
A. methylation
To determine the genotype of a pea plant with purple flowers it was crossed with a pea plant with white flowers. Half of the offspring exhibited the dominant purple flower while the other half had white flowers. What was the genotype of the parental pea plant with the purple flowers?
A. can’t be determined
B. homozygous recessive
C. heterozygous
D. homozygous dominant
C. heterozygous
The failure of chromosomes to separate during anaphase is called __________.
A. nondisjunction
B. synapsis
C. epistasis
D. maternal effect
A. nondisjunction
Trisomy 8 usually leads to the early miscarriage of a fetus. However, adult individuals have been found with cells that have three copies of chromosome 8 in them. How can this be?
A. The trisomic 8 adults likely have a mosaic region with trisomy 8.
B. This individual must be triploid.
C. The trisomic cells underwent complete nondisjunction.
D. The trisomic cells underwent a meiotic nondisjunction.
A. The trisomic 8 adults likely have a mosaic region with trisomy 8.
Two genes that are located on the same chromosome are said to be _____.
A. linked
B. recombinant
C. parental-like
D. nonparental-like
A. linked
Another name for a chromosome is a _______, since it contains genes that are often inherited together.
A. linkage group
B. crossing over group
C. genetic recombinant
D. bivalent
A. linkage group
Which of the following defines gene linkage?
A. Two or more genes that are physically connected on a chromosome.
B. Genes that are transmitted to the next generation as a group.
C. The process by which genetic information is exchanged between homologous chromosomes.
D. All of these choices are correct.
E. Both two or more genes that are physically connected on a chromosome and genes that are transmitted to the next generation as a group.
E. Both two or more genes that are physically connected on a chromosome and genes that are transmitted to the next generation as a group.
In humans, there are _______ autosomal linkage groups, plus an X and Y chromosome linkage group.
A. 23
B. 46
C. 92
D. 22
D. 22
Which of the following is not one of the properties of gene linkage that Morgan obtained from his experiments?
A. Genes that are on the same chromosome are always transmitted together as a unit.
B. Crossing over exchanges pieces of chromosomes and creates new allele combinations.
C. Genes that are on the same chromosome may be inherited together.
D. The likelihood of crossing over occurring between two genes is dependent on the distance of the genes from one another.
A. Genes that are on the same chromosome are always transmitted together as a unit.
The formula p^2 + 2pq + q^2 = 1 is associated with which of the following
A. calculations of heterozygosity
B. Hardy-Weinberg equilibrium
C. calculations of recombination frequencies
D. degrees of freedom
E. None of these choice are correct
B. Hardy-Weinberg equilibrium
In the equation p2 + 2pq + q2 = 1, what does the term 2pq represent?
A) the genotypic frequency of homozygous recessive individuals
B) the genotypic frequency of homozygous dominant individuals
C) the genotypic frequency of heterozygous individuals
D) the sum of the phenotypic frequencies in the population
E) None of these choices are correct.
C) the genotypic frequency of heterozygous individuals
Natural selection occurs when
A) humans breed certain individuals with the most desirable phenotypes.
B) the genotype of an individual does not determine whether or not is has reproductive success.
C) individuals whose phenotypes are best suited for environmental conditions have lower reproductive success but live longer.
D) individuals whose phenotypes are best suited for environmental conditions have higher reproductive success and contribute more alleles to the next generation.
D) individuals whose phenotypes are best suited for environmental conditions have higher reproductive success and contribute more alleles to the next generation.
Select the definition of genetic drift.
A. Changes in genome size in a species due to random mutations
B. Changes in genotype frequencies in a population due to new mutations
C. Changes in allele frequencies in a population due to migration
D. Changes in allele frequencies in a population due to random fluctuations
D. Changes in allele frequencies in a population due to random fluctuations
The mechanism that results in a change in allele frequencies due to random processes is known as?
A. genetic drift
B. natural selection
C. migration
D. non random mating
A. genetic drift
A _______ translocation occurs when a piece of one chromosome is attached to another chromosome.
A. balanced
B. complex
C. simple
D. reciprocal
C. simple
Which of the following generally has the least effect on the phenotype of the individual who carries it?
A. Robertsonian translocation
B. unbalanced translocation
C. balanced translocation
D. All of these choices are equally detrimental to the phenotype
C. balanced translocation
A phenotypically normal person is having fertility issues. They consult a geneticist. Their karyotype shows they have 45 chromosomes. Which of the following is the most likely cause of their chromosome abnormality?
A. Inversion
B. Robertsonian translocation
C. Partial deletion
D. Balanced translocation
B. Robertsonian translocation
A translocation cross may occur in an individual which has which of the following?
A) reciprocal translocation
B) unbalanced translocation
C) simple translocations
D) All of these choices are correct.
A) reciprocal translocation
The term _______ refers to genetic differences between members of the same species.
A. chromosomal variation
B. chromosomal deletions
C. genetic variation
D. polyploidy
C. genetic variation
A loss of an internal portion of a chromosome is called a(n) __________.
A) terminal deficiency
B) interstitial deletion
C) reciprocal translocation
D) gene duplication
B) interstitial deletion
Given the following sequence of genes on a chromosome, determine what change in chromosome structure occurred. The asterisk (*) indicates the centromere.
Before: A B C D * E F G H
After: A C D * E F G H
A. interstitial deletion
B. terminal deletion
C. gene duplication
D. recombination
A. interstitial deletion
Given the following sequence of genes on a chromosome, determine what change in
chromosome structure occurred. The asterisk (*) indicates the centromere.
Before: A B C D * E F G H
After: A B G F E * D C H
A) reciprocal translocation
B) pericentric inversion
C) paracentric inversion
D) gene duplication
E) None of the answers are correct.
B) pericentric inversion
Inversion loops can occur in which of the following?
A. reciprocal translocations
B. paracentric inversions
C. pericentric inversions
D. gene duplications
E. both paracentric inversions and pericentric inversions
E. both paracentric inversions and pericentric inversions
Calculate the narrow sense heritability for a grandparent-grandchild relationship when the observed correlation coefficient is 0.2.
A. 0.8
B. 2.5
C. 0.4
D. 1.25
A. 0.8
Calculate the narrow-sense heritability of height between aunts and nieces if the observed phenotypic correlation coefficient is 0.1
A. 2.5
B. 0.25
C. 4
D. 0.4
D. 0.4
Which process uses a bacteriophage as an intermediary for the genetic information?
A. fission
B. transformation
C. conjugation
D. transduction
D. transduction
Represents a mechanism of genetic transfer in bacteria.
A. Transformation
B. Transduction
C. Conjugation
D. All of the answers are correct
D. All of the answers are correct
Can occur either as a lytic or lysogenic cycle.
A. Transformation
B. Transduction
C. Conjugation
D. All of the answers are correct
B. Transduction
Which does not require any recombination with the bacterial chromosome?
A. transduction
B. transformation
C. conjugation
C. conjugation
DNA transfer via a physical connection between bacteria is known as
A. conjugation
B. transformation
C. transduction
D. fission
A. conjugation
When a bacteria assimilates genetic material (DNA) directly from the environment, this is called
A. transduction.
B. fission.
C. conjugation.
D. transformation
D. transformation
Bacterial cells that can participate in ______ are known as competent cells.
A. transduction
B. fission
C. conjugation
D. transformation
D. transformation
Uses competent cells.
A. Transformation
B. Transduction
C. Conjugation
D. All of the answers are correct
A. Transformation
A cell with an F factor integrated into the bacterial chromosome is called __________.
A. Hfr
B. a conjugative plasmid
C. F+
A. Hfr
Which of the following matings would have the highest frequency of chromosomal gene transfer?
A. F+xF-
B. F’xF-
C. Hfr x F-
C. Hfr x F-
During a phage life cycle sometimes a phage is packaged carrying a portion of the host cell chromosome, which results in transduction. During conjugation, which plasmid can most directly be compared to the phage that carries a fragment of the host cell chromosome?
A. F’ factor
B. F factor
C. R factor
D. Col-plasmid
A. F’ factor
Which of the following expressions denotes a trisomic organism?
A) 3n
B) 2n+1
C) 2n+2
D) 2n-1
B) 2n+1
A diploid organism has a total of 36 chromosomes. Assuming all possible chromosome combinations are viable, if a mutant tetraploid version of this organism was created how many chromosomes would it have? If a mutant version of the diploid organism was monosomic for chromosome 9 how many chromosomes would it have?
A. 144; 35
B. 72; 35
C. 72; 37
D. 144; 37
B. 72; 35
Which of the following describes an organism with two complete sets of chromosomes from two different species?
A. allodiploid
B. tetraploid
C. aneuploid
D. allotetraploid
D. allotetraploid
Which type of plant would usually be a seedless variety
A. aneuploid
B. triploid
C. diploid
D. tetraploid
B. triploid
A bacteriophage that is physically integrated into the host chromosome is called a ________.
A. prophage
B. heteroduplex
C. envelope phage
D. plaque
A. prophage
A _______ uses the lytic cycle to begin the immediate manufacture of new phages in the host cells.
A. eukaryotic cell
B. temperate phage
C. virulent phage
D. bacteria
C. virulent phage
A _______ frequently integrates into the host genome, forming prophages and utilizing a lysogenic cycle to manufacture new phages.
A. eukaryotic cell
B. virulent phage
C. temperate phage
D. bacteria
C. temperate phage
Which virus uses reverse transcriptase in its reproductive cycle?
A. HIV
B. Phage lambda
C. Both of the viruses use reverse transcriptase
D. Neither of the viruses use reverse transcriptase
A. HIV
Which enzyme is unique to the retro elements?
A. Reverse transcriptase
B. Reverse resolvase
C. Transposase
D. Integrase
E. Reverse integrase
A. Reverse transcriptase
What is true in both phage λ and HIV infections?
A. Cell lysis always occurs immediately after virus introduction.
B. There can be a long latent period where no sign of infection, such as cell death, is detectable.
C. Assembled viral particles are always found within the cell.
B. There can be a long latent period where no sign of infection, such as cell death, is detectable.
Vaccines have been very useful in preventing viral diseases. In fact, they have lead to the eradication of smallpox from the world’s human population. Most vaccines result in the host producing antibodies (proteins that bind to specific amino acid sequences) that bind to specific viral proteins. What might be a reason why a vaccine for HIV has been so difficult to develop?
A. The low mutation rate of HIV
B. The fact that HIV genome is found as both DNA and RNA in a cell
C. The high mutation rate of HIV
D. The HIV virion is coated with cellular proteins
C. The high mutation rate of HIV
Following transcription, the RNA has a complementary sequence to
A. the coding strand of DNA
B. termination sequences
C. the template strand of DNA
D. regulatory sequences
C. the template strand of DNA
Which of the following best describes the mechanism of DNA replication in which both parental strands remain together following replication?
A. Dispersive
B. Semi-conservative
C. Conservative
D. All of the answers are correct
C. Conservative
Which describes the mechanism of DNA replication in which the newly made double-stranded DNA contains one parental strand and one daughter strand?
A. semiconservative
B. conservative
C. dispersive
A. semiconservative
You have isolated what appears to be alien DNA. While studying its replication, you performed the exact experiment Meselson and Stahl did. After three generations, the DNA is subjected to a CsCl gradient and only one band appears. What type of replication does this DNA undergo?
A. Semiconservative
B. Conservative
C. Dispersive
C. Dispersive
During a retrotransposition event, 4 DNA copies of a retrotransposon are created. At the end of this event, how many total copies of the retrotransposon will be found in the genome?
A. 1
B. 5
C. 10
D. 8
E. 4
B. 5
Transposons that use an RNA intermediate for transposition are called _____.
A) RNAi transposons
B) R elements
C) retrotransposons
D) reverse transposons
C) retrotransposons
Long-terminal repeats are unique to which group of transposons?
A. integrase
B. non-LTR retrotransposons
C. simple transposons
D. LTR retrotransposons
D. LTR retrotransposons
The correct order of compaction from least compacted to most compacted would be
A. naked DNA, nucleosome, 30 nm fiber, loop, metaphase chromosome.
B. naked DNA, loop, 30 nm fiber, nucleosome, metaphase chromosome.
C. naked DNA, 30 nm fiber, nucleosome, loop, metaphase chromosome.
D. naked DNA, metaphase chromosome, loop, 30 nm fiber, nucleosome.
A. naked DNA, nucleosome, 30 nm fiber, loop, metaphase chromosome.
What is the first level of chromosome compaction among the following choices?
A. closer association of loop domains
B. 30 nm fibers
C. loop domains
D. nucleosomes
D. nucleosomes
DNA helicase enzymes move in what direction along the DNA during DNA replication?
A. 5’ to 3’
B. 3’ to 5’
C. They remain stationary
A. 5’ to 3’
Topoisomerase I does which of the following?
A. relax negative supercoils
B. introduce negative supercoils
C. More than one of these choices are correct.
D. relieve positive supercoils
A. relax negative supercoils
What enzyme relaxes supercoiling ahead of the replication fork?
A. DNA polymerase I
B. DNA primase
C. DNA polymerase III
D. topoisomerase
D. topoisomerase
Which of the following is an example of a processive enzyme?
A. DNA polymerase I
B. DNA polymerase III
C. DNA ligase
D. Okazaki fragments
B. DNA polymerase III
DNA polymerase III carries out leading and lagging strand synthesis in prokaryotes. How many enzymes accomplish this task in eukaryotes (not counting primer creation)?
A. three
B. one
C. four
D. two
D. two
Which enzyme synthesizes the lagging strand of the DNA?
A. DNA polymerase I
B. DNA polymerase III
C. Topoisomerase
D. DNA primase
B. DNA polymerase III
Which enzyme is responsible for the majority of DNA synthesis during replication?
A. DNA polymerase I
B. DNA polymerase III
C. DNA primase
D. DNA ligase
E. topoisomerase
B. DNA polymerase III
Which enzyme attaches adjacent Okazaki fragments, forming a continuous DNA strand?
A. topoisomerase
B. DNA primase
C. DNA polymerase III
D. DNA ligase
E. DNA polymerase I
D. DNA ligase
Which answer would best represent the composition of double stranded DNA?
A.
15% A
25% G
15% C
35% T
B.
20% A
20% G
20% C
40% T
C.
30% A
15% G
15% C
30% T
D.
20% A
20% G
30% C
30% T
C.
30% A
15% G
15% C
30% T
Choose the RNA molecule that would be complementary to this DNA molecule: 5’-TTAACCGG-3’.
A. 5’-UUAACCGG-3’
B. 5’-AAUUGGCC-3’
C. 3’-AATTGGCC-5’
D. 3’-AAUUGGCC-5’
D. 3’-AAUUGGCC-5’
In eukaryotic organisms, a functional eukaryotic protein is typically made up of the information contained within what region of pre-mRNA?
A. introns
B. enhancers
C. exons
D. promoters
C. exons
In eukaryotic organisms, alternative splicing allows an organism to ___________.
A. produce only one protein from a gene.
B. produce nonfunctional variants of proteins from a gene
C. produce several different proteins from a single gene.
C. produce several different proteins from a single gene.
In eukaryotic organisms, what RNA modification is important for mRNA stability?
A. base modification
B. 3’ polyA tailing
C. RNA editing
D. processing
B. 3’ polyA tailing
In eukaryotic organisms, what process is important for the initiation of translation?
A. alternative splicing
B. 5’ capping
C. RNA editing
D. base modification
B. 5’ capping
Which modifications are typically found on eukaryotic mRNAs?
A. Eukaryotic mRNAs are not modified before translation
B. Addition of poly A only
C. Capping only
D. Capping and poly-A addition
D. Capping and poly-A addition
A tRNA that has an amino acid attached is called _____.
A. rRNA
B. degenerate tRNA
C. coding tRNA
D. charged tRNA
E. None of the answers are correct.
D. charged tRNA
Which molecule contains an anticodon?
A. mRNA
B. rRNA
C. snRNA
D. DNA
E. tRNA
E. tRNA
What is the minimal number of tRNAs that can be used to recognize all of the codons for threonine?
A. 4
B. 3
C. 1
D. 2
D. 2
In bacteria, the sequence that facilitates the binding of the mRNA to the ribosome is called the
A. Kozak sequence.
B. rRNA sequence.
C. Shine-Dalgarno sequence.
D. start sequence.
C. Shine-Dalgarno sequence.
Kozak’s rules for translation are similar to those for transcription in prokaryotes in that they both contain consensus sequences. In prokaryotes, the promoter consensus sequences are at −35 and −10. Where is the consensus sequence for translational initiation according to Kozak’s rules?
A. −12 to −2
B. −35 to −10
C. +1 to +10
D. −6 to +4
D. −6 to +4
T or F: A mutation is a change in DNA sequence and must be inheritable
TRUE
What is the difference between genetic testing and genetic screening?
A. Genetic testing is concerned more with individuals and genetic screening is concerned with populations.
B. Genetic screening is concerned more with individuals and genetic testing is concerned with populations.
C. They use different tests and techniques to detect genetic mutations.
D. Genetic testing is concerned more with nonlethal syndromes and diseases, and genetic screening is concerned with lethal diseases and syndromes.
A. Genetic testing is concerned more with individuals and genetic screening is concerned with populations.
In the United States, most newborns undergo a test for primary congenital hypothyroidism, a condition where people are unable to produce enough thyroid hormone. On a nationwide basis, this is an example of __________.
A. genetic testing
B. preimplantation genetic diagnosis
C. amniocentesis
D. genetic screening
D. genetic screening
The process of _______ removes amniotic fluid from a pregnant mother to examine fetal cells for genetic problems.
A. chorionic villus sampling
B. in vitro fertilization
C. amniocentesis
D. preimplantation genetic diagnosis
C. amniocentesis
Which environmental agent shown can induce mutations?
A. UV radiation
B. X-rays
C. gamma rays
D. All of the answers are correct.
D. All of the answers are correct.
CpG islands are associated with which of the following?
A. DNA methylation
B. steroid hormone activity
C. termination of translation
D. nucleosome location
A. DNA methylation
T or F: constitutive is expressed continuously at constant levels of expression?
TRUE
A gene is inducible and under negative control. Which of the following pairs will allow expression of this gene?
A. activator + inhibitor
B. activator + repressor
C. repressor + inducer
D. repressor + corepressor
C. repressor + inducer
What are the general ways that tumor suppressors and oncogenes act?
A. Tumor suppressors inhibit the cell cycle and oncogenes stimulate the cell cycle.
B. Oncogenes inhibit the cell cycle and tumor suppressors stimulate the cell cycle.
C. Both tumor suppressors and oncogenes stimulate the cell cycle.
D. Both tumor suppressors and oncogenes inhibit the cell cycle.
A. Tumor suppressors inhibit the cell cycle and oncogenes stimulate the cell cycle.
If a point mutation increases the number of offspring an organism can produce, it would be called a _____ mutation.
A. deleterious
B. conditional
D. lethal
E. neutral
F. beneficial
F. beneficial
Consider the following DNA sequence, which codes the first portion of a long protein beginning at the ATG (AUG in mRNA) start codon.
5’ ATG CCC CGC AGT AGG GGG TGG AGA 3’
Which of the mutated sequences listed is most likely to be a deleterious mutation?
A) 5’ ATG CCC CGC AGT AGG GGG TGA AGA3’
B) 5’ ATG CCG CGC AGT AGG GGG TGG AGA3’
C) 5’ ATG CCC CGC AGT AGG GAG TGG AGA3’
C) 5’ ATG CCC CGC AGT AGG GAG TGG AGA3’
Which types of mutations are least likely to be subjected to natural selection?
A. Insertion
B. Nonsense
C. Missense
D. Silent
D. Silent
A translocation that moves a gene from an area of euchromatin to heterochromatin would typically cause _____ in the expression of the gene.
A. no change
B. an increase
C. a reduction
C. a reduction
Regions of chromatin that are more compact are called __________; they are usually found __________ in the nucleus.
A. euchromatin; centrally
B. euchromatin; at the periphery
C. heterochromatin; centrally
D. heterochromatin; at the periphery
D. heterochromatin; at the periphery
Antisense RNA does which of the following?
A. binds to a complementary RNA and prevents its translation
B. occupies the A and P sites of the ribosome
C. inhibits the formation of the open complex in transcription
D. prevents the correct folding of a newly formed peptide
A. binds to a complementary RNA and prevents its translation
Acetylation of histones results in
A. formation of a closed chromatin structure.
B. termination of transcription.
C. removal of histones from the histone octamer.
D. formation of an open chromatin structure.
D. formation of an open chromatin structure.
T or F: Activator -> Enhancer and Repressor -> Silencer
TRUE
According to Chargaff’s rule, if the DNA of a species contains 20% adenine, what percent of guanine will it contain?
A. 50%
B. 75%
C. 20%
D. 30%
D. 30%
Enzymes involved in metabolism are most likely regulated via _____.
A. feedback inhibition
B. acetylation
C. methylation
D. None of the answers are correct.
A. feedback inhibition
In a given population of Drosophila, curly wings (c) is recessive to the wild-type condition of straight wings (c+). You isolate a population of 35 curly winged flies, 70 flies that are heterozygous for straight wings, and 45 that are homozygous for straight wings. What is the frequency of alleles in this population?
A. 35% c; 45% c+
B. 46.7% c; 53.3% c+
C. 50% c; 50% c+
D. 55% c; 45% c+
E. None of these choices are correct.
B. 46.7% c; 53.3% c+
What is the frequency of an allele in a conglomerate population if 50 individuals from a population where the allele has a frequency of 0.6 migrates into a population of 450 individuals where the allele frequency is 0.3?
A. 0.3
B. 0.33
C. 0.18
D. 0.9
B. 0.33
Red-green colorblindness is a X-linked recessive trait in humans. If a woman who is a carrier for red-green colorblindness marries a normal male, what percent of their sons will be colorblind?
A) 100%
B) 50%
C) 25%
D) 0%
B) 50%
If the difference between the mean of the parents and the mean of the starting population is 1.0 and the difference between the mean of the offspring and the mean of the starting population is 0.45 then the realized heritability is
A. 0.45
B. 2.22
C. 0.56
D. 1.45
A. 0.45
A selective breeding program is trying to develop an agricultural plant with decreased stem length to aid in mechanical harvesting. The mean stem height of the population is 36 cm while the mean stem height of the parents is 30 cm and the mean stem height of the offspring is 33 cm. What is the realized heritability for stem height in this crop?
A. 0.33
B. 0
C. 1
D. 0.5
D. 0.5
A selective breeding program is trying to develop an agircultural plant with decreased stem length to aid in mechanical harvesting. The mean stem height of the popluation is 36 cm while the mean stem height of the parents is 30 cm and the mean stem height of the offspring is 33 cm. What is the realized heritability for stem height in this crop?
A. 1
B. 3
C. -3
D. 0.1
A. 1
Given the allele frequency for a gene in population A is 0.3 and the frequency for the same alleles in population B is 0.5 and that 25 individuals from A migrate to and mate randomly with the 475 individuals in population B, what is the new allele frequency (P_C) in the conglomerate?
A. 0.2
B. 0.49
C. 0.052
D. 0.8
B. 0.49
If the allele frequency of the dominant allele is 0.4, what value is used for the term p2 in the equation p2 + 2pq + q2 = 1?
A. 0.16
B. 16
C. 0.2
D. 0.4
A. 0.16
The diploid garden pea plant has 14 chromosomes. The haploid fungus Neurospora crassa has 7 chromosomes. Neither organism has separate male and female individuals. Therefore, the number of linkage groups in these two organisms is
A. Garden pea has 14 linkage groups, and Neurospora has 7.
B. Garden pea has 7 linkage groups, and Neurospora has 7.
C. Garden pea has 8 linkage groups, and Neurospora has 8.
D. Garden pea has 15 linkage groups, and Neurospora has 8.
B. Garden pea has 7 linkage groups, and Neurospora has 7.
Genetic variation is ultimately based upon which of the following?
A) translation
B) carbohydrate content of the cell
C) morphological differences
D) variations in nucleotide sequence of the DNA
D) variations in nucleotide sequence of the DNA
A diploid cell in G1 contains 5 pairs of chromosomes. During mitosis, how many chromosomes will be lined up on the metaphase plate in this cell?
A) 15
B) 10
C) 5
D) 20
B) 10
Consider a tree in which in thick trunk (T) is dominant to a skinny trunk (t), back bark (B) is dominant to brown bark (b) and round leaves (R) are dominant to oval leaves (r). You cross a tree that is heterozygous for all three traits to a tree that is homozygous recessive for all three traits. Using the forked line method or the multiplication method, calculate what fraction of the offspring will have a thick trunk, black bark, and round leaves.
A) 1/4
B) 1/2
C) 1/8
D) 1/16
C) 1/8
In cattle, the scurs trait follows a sex-influenced pattern of inheritance. A heterozygous male has the _______ phenotype and a heterozygous female has a _______ phenotype.
A) hornless; scurs
B) scurs; hornless
C) hornless; hornless
D) scurs; scurs
B) scurs; hornless
Consider a bird in which a high-pitched song (H) is dominant to a low-pitched song (h). You cross two birds that are heterozygous for the gene for song pitch. Predict the genotypes and phenotypes of the offspring.
A. 1/4 HH: 1/2 Hh: 1/4 hh; 3/4 high-pitched song: 1/4 low-pitched song
B. 1/2 HH: 1/2 hh; 1/2 high-pitched song: 1/2 low-pitched song
C. 1/4 HH: 1/2 Hh: 1/4 hh; 1/2 high-pitched song: 1/2 low-pitched song
D. All Hh; All high-pitched song
A. 1/4 HH: 1/2 Hh: 1/4 hh; 3/4 high-pitched song: 1/4 low-pitched song
Brown spotting of the teeth in humans is caused by a dominant X-linked gene. If a man with normal teeth marries a woman with brown teeth who had a father with normal teeth, then _______ of their daughters will have brown teeth.
A. 50%
B. 0%
C. 25%
D. 100%
A. 50%
In four-o’clock plants, red flower color is dominant to white flower color. However, heterozygous plants have a pink color. If a pink-flowered plant is crossed with a white-flowered plant, what will be the phenotypic ratios of their offspring?
½ pink, ½ white
Recall that scurs in cattle that exhibit sex-influenced inheritance. There are two alleles ScP, which represents scurs being present and ScA, which indicates scurs being absent. ScP is dominant in males and recessive in females. ScA is dominant in females and recessive in males. From a mating between a heterozygous male with scurs and a heterozygous female without scurs, what proportion of male offspring will lack scurs (be hornless)?
25%
Recall that in pea plants, purple flower color is dominant and white is recessive. If two heterozygous plants are crossed, what is the probability that the first two offspring will have purple flowers?
9/16
