Ecol
The RNA-protein complex that targets proteins for secretion is called the .
Blank 1: signal Blank 2: recognition Blank 3: particle
The genetic material of HIV consists of two -stranded molecules.
Blank 1: single Blank 2: RNA
Mutations can be caused in two main ways: (1) mutations are the result of natural biological or chemical processes; and (2) mutations are produced by environmental agents.
Blank 1: spontaneous Blank 2: induced
During embryonic development, many genes within a specific cell type will undergo epigenetic changes that enable them to be or cause them to be permanently .
Blank 1: transcribed or expressed Blank 2: repressed or silenced
A segment of DNA that can become integrated into chromosomes is called a(n) .
Blank 1: transposable Blank 2: element
Select all that apply Which of the following are examples of epigenetics?
DNA methylation Chromatin remodeling Localization of histone variants Covalent histone modification
DNA sequencing enables researchers to determine the order of ______ ______ in a gene.
DNA nucleotides
Phage DNA that is integrated into the chromosome of a bacterial cell is called a(n)
prophage
Where are PIWI proteins primarily expressed?
Germ-line cells
The ncRNA Hox transcript antisense intergenic RNA is also known as
HOTAIR
The first proposal for a set of steps at the molecular level that lead to homologous recombination is called the model.
Holliday
Which model for recombination involves production of single-strand breaks in each of the non-sister chromatids after which the strands invade the opposite helices?
Holliday model
True or false: High levels of HOTAIR expression in breast tumors are a significant predictor of death, but the cancer causing mechanism of HOTAIR is not well understood.
True
True or false: When phage λ infects a bacterial cell, the activation of PL and PR initiates a competition between the lysogenic and lytic cycles.
True
What role do miR-200 family members play with regard to cancer?
Tumor suppressor
Select all that apply What types of worms were compared in the Mello and Fire experiment?
Uninjected worms Worms injected with antisense RNA alone Worms injected with double-stranded RNA
Select all that apply Which of the following statements about promoter mutations is true?
Up promoter mutations cause the promoter sequence to be more like the consensus sequence Down promoter mutations decrease the affinity of transcription factors to the promoter
What is a provirus?
Viral DNA integrated into a chromosome in a eukaryotic cell
Select all that apply What happens during the lysogenic cycle?
Viral DNA is incorporated into the host cell's chromosome. New phages are not made.
What technique is used to identify a particular protein in a mixture of proteins?
Western blotting
Homologous recombination is a process in which
a new combination of DNA sequences is formed through breakage and rejoining of similar or identical DNA segments.
Base excision repair (BER) is the main system used in the repair of ______.
abnormal bases
Because a bacterial cell must first be exposed to an agent to elicit a response, the CRISPR-Cas system is called a(n) ______.
adaptive defense system
A mutagen is a(n) ______.
agent that causes mutations
The term germ line is used to describe the ______.
cells that produce sperm and eggs
A silent mutation is a mutation that results in no ______.
change to the amino acid sequence of the polypeptide
A particular gene to be cloned is often isolated from ______.
chromosomal DNA
Which type of epigenetic mechanism is shown in the image?
cis-epigenetic mechanism
You would a gene to make many copies of that gene.
clone or amplify
A DNA molecule that acts as a carrier of DNA that is to be cloned is called a(n) ______.
cloning vector
In PCR, primer extension refers to the synthesis of ______ starting at the primers.
complementary DNA
During the interference phase of the CRISP-Cas defense system, each spacer within a ______ is complementary to one of the strands of the bacteriophage DNA.
crRNA
Restriction endonucleases are used in gene cloning to ______.
cut the DNA backbone prior to inserting the DNA to be cloned
Nitrous acid is a mutagen that acts via the process of ______.
deamination
The removal of a purine from DNA is called
depurination or depurinization
Mutations that remove an adenine or guanine from the DNA are known as ______.
depurinations
Reverse transcriptase PCR can be used to ______.
detect and quantify the amount of a specific RNA.
The DNA sequencing method developed by Frederick Sanger that became a commonly used method of DNA sequencing is called sequencing.
dideoxy
Photoreactivation is a repair mechanism that can ______ a thymine dimer in the ______ of light.
directly split; presence
Alkylating agents cause mutations by ______.
disrupting the normal pairing between nucleotides within the DNA
Phage λ, a virus that infects bacterial cells, has a genome made of ______.
double-stranded DNA
Which ncRNA or ncRNA processing protein is associated with Familial amyotrophic lateral sclerosis?
drosha
The gel retardation assay is also known as the ______.
electrophoretic mobility shift assay
A virus that has arisen recently and is therefore more likely to cause infection than previous strains is called a(n) virus.
emerging
Human immunodeficiency virus is a(n) ______ virus with a(n) ______ genome.
enveloped; RNA
The inactivation of an X chromosome is a(n) ______ event.
epigenetic
DNA methylation, chromatin remodeling, covalent histone modification, and localization of histone variants are all examples of molecular mechanisms that are involved in .
epigenetics or epigenetic
The variation of gene expression that is not related to the variation of the DNA, is transmissible, and is reversible is described as
epigenetics, epigenetic, or epimutation
In bacteriophages, the term lysogeny is often used in place of the word ______.
latency
If the genetic material of a human virus is replicated as part of a chromosome or as an episome without the production of new virus particles, the virus is said to be .
latent, dormant, or inactive
Translesion DNA polymerases are ______ accurate and ______ sensitive to geometric distortions in DNA than replicative DNA polymerases.
less ; less
In PCR, the temperature must be ______ from the denaturation temperature in order for primers to anneal.
lowered
If the integrase gene is activated after bacteriophage λ infects bacterial cell, then the phage will enter the cycle.
lysogenic
The viral reproductive cycle in which bacteriophage DNA is incorporated into the host cell's DNA but new phages are not made immediately is called the cycle.
lysogenic
In bacteriophages, another term for latency is
lysogeny
In a bacterial cell infected with phage λ, if the activity of the cro protein is greater than the activity of the cII protein, then the cycle will occur.
lytic
Abnormal expression levels of have been found in early all neurological disorders in which they have been investigated.
miRNAs
Levels of expression of which type of ncRNAs have been found to differ between normal and cancer cells in nearly all forms of human cancer?
miRNAs
To date, most research on ncRNAs as targets for therapy has been on ______.
miRNAs and cancer
An agent that can change DNA structure and cause mutations is known as a(n) .
mutagen or mutagens
An allele that has a DNA sequence different from that of the wild-type is called a(n) allele.
mutant
A heritable change in the genetic material is called a(n) ______.
mutation
The term refers to an inherited change in the sequence of the genetic material.
mutation
snoRNAs are found in high amounts in the ______.
nucleolus
The term "host range" describes the ______ by a virus.
number/type of species that can be infected
The lncRNA HOTAIR acts as a(n) in cancer, and is highly expressed in a variety of cancers.
oncogene
The process by which thymine dimers are directly repaired with the help of light is called
photoreactivation
Match the ncRNA with the disease with which it is associated.
piRNAs matches Choice, Testicular cancer snoRNAs matches Choice, Lung cancer miRNAs matches Choice, Alzheimer disease miR-200 family matches Choice, Bladder cancer
A small circular DNA molecule that is often used as a vector in gene cloning is called a(n)
plasmid or plasmids
A change of one base for another is described as a base mutation.
point
In order for HIV to be incorporated into the host cell genome, a ______ complex of HIV DNA and proteins forms in the cytoplasm and is then transported to the nucleus.
preinitiation
Short oligonucleotides that flank the region of DNA to be amplified by PCR are called
primer
Activation of the transcription factor NF-κB in a cell containing the HIV provirus results in ______.
production of new viral particles
Phage DNA that is integrated into the chromosome of a bacterial cell is called a(n) .
prophage
A key function of snoRNAs is to covalently modify
rRNAs or rRNA
The number of species and cell types that a virus can infect is called its host
range
Oxidative DNA damage refers to changes in DNA structure that are caused by ______.
reactive oxygen species
What is the technique that allows one to determine the amount of template DNA present when the PCR cycles began?
real-time PCR
If a heteroduplex includes a region with an allelic difference, the cell will ______.
repair the mismatch to either the dominant or recessive allele
The CRISPR locus in prokaryotes contains a series of ______.
repeated sequences
The natural function of the CRISPR-Cas system in bacteria is to ______.
to provide defense against bacteriophages
The process by which a transposable element is integrated into a new site in the genome is called ______.
transposition
Select all that apply CRISPR-Cas systems provide a defense against ______.
transposons bacteriophages plasmids
True or false: Chromosomal DNA is a common source of cloned DNA.
true
True or false: Most DNA repair systems involve three major steps: detection of the error, removal of the abnormality, and its replacement with normal DNA.
true
A small DNA molecule that can replicate independently within a host cell and thus make many copies of an inserted gene is called a
vector
A nonliving infectious particle with a genome composed of nucleic acid is called a(n)
virus
You wish to determine if a protein is made at a particular stage of development. What technique would you use?
western blotting
A breakpoint refers to the region ______.
where two chromosome pieces break and rejoin with other chromosome pieces
The annual flowering plant Arabidopsis thaliana has two different types. Only the ______ require vernalization for flowering.
winter annuals, which grow from fall to spring,
In addition to the DNA strands of the chromosomes involved in homologous recombination, the multiple steps in the pathway require the action of
protein catalysts.
Viral DNA that is integrated into a chromosome in a eukaryotic cell is called a(n)
provirus
In the CRISPR-Cas defense system, what triggers the expression phase?
A subsequent bacteriophage infection
What is an emerging virus?
A virus that has arisen recently and is likely to cause infection
What is a retrovirus?
A virus with a genome made of RNA that copies its genome by reverse transcription
The viral enzyme that uses a viral RNA strand as a template for the synthesis of a complementary copy of DNA is called .
Blank 1: reverse Blank 2: transcriptase
The enzyme is used when PCR is employed to detect and quantify the amount of a specific RNA.
Blank 1: reverse or reverse transcriptase Blank 2: transcriptase
The phenomenon in which a repeated sequence of three nucleotide bases increases in number generation after generation is called .
Blank 1: trinucleotide Blank 2: repeat Blank 3: expansion
Mutations that occur in a promoter sequence can be divided into two types: promoter mutations increase the transcription rate, while promoter mutations decrease it.
Blank 1: up Blank 2: down
The mutagen nitrous acid changes cytosine and adenine to
Blank 1: uracil Blank 2: hypoxanthine
Select all that apply During adaptation, what proteins in the CRISPR-Cas system are involved in recognizing and cleaving bacteriophage DNA into small pieces?
Cas2 Cas1
During the interference phase, which protein in the CRISPR-Cas system cleaves bacteriophage DNA?
Cas9
Which component in the CRISPR-Cas9 system makes a double-strand break in DNA?
Cas9
Dideoxy sequencing was formulated based on scientists' knowledge of what process?
DNA replication
Select all that apply Which of the following therapies restores miRNA function?
Enhancing function of the miRNA processing machinery Use of DNA demethylating agents and histone deacetylase inhibitors
Select all that apply Which of these are examples of alkylating agents?
Ethyl methanesulfonate Nitrogen mustard
Match the phase of real-time PCR with the accumulation of products.
Exponential matches Choice, The amount of product nearly doubles with each cycle but may be difficult to detect as the amounts are small. Linear matches Choice, Accumulation of the product shows a directly proportional relationship to cycle number. Plateau matches Choice, Accumulation of the product levels off as one or more reagents are used up.
Which phase of the CRISPR-Cas defense system is depicted in this figure?
Expression
Physical mutagens include ______.
both X-rays and UV light
The methylation of a previously unmethylated site is called ______.
de novo methylation
In gene cloning, what is the vector?
A small DNA molecule that can replicate independently within a host cell
What is a plasmid?
A small circular DNA molecule often used as a vector in gene cloning
Click and drag on elements in order List the steps of how a gene may be targeted for silencing by PcG complexes in the correct sequence, putting the first step on top.
1. PRE 2. PRC2 3. Transcription
Click and drag on elements in order Order the following steps in cloning a gene, putting the first step at the top.
1. chromosomal 2. the digestion 3. ligation
Click and drag on elements in order Order the steps in one cycle of a PCR reaction, putting the first step at the top.
1. denaturation 2. primer annealing 3. primer extension
Click and drag on elements in order Place the steps that occur during the reproductive cycle of phage λ in the correct order, putting the first step at the top.
1. phage binds 2. phage dna 3. viral 4. phage components
Click and drag on elements in order List the steps of RNA interference in the correct sequence.
1. pre 2. double 3. one 4. single 5. RISC
Arrange the steps that occur when HIV infects an animal cell in the correct order, putting the first step at the top.
1. spike 2. the viral envelope 3. the viral capsized 4. cellular 5. RNA
Click and drag on elements in order Order the genes commonly found in the CRISPR-Cas type II system. Start with tracr at the top.
1. tract 2. cas9 3. cas1 4. cas2 5. crisps
Translesion DNA polymerases incorporate wrong nucleotides with a frequency of approximately _____, which is ______ than the error rate for replicative DNA polymerases.
10-2 ; higher
Approximately how many human genes are estimated to encode miRNAs?
2,000
When pre-piRNA is processed, the resulting piRNAs are ______ nucleotides in length.
24-31
What percentage of human protein-encoding genes are thought to be regulated by miRNAs?
60%
What percentage of miRNAs are expressed in the brain?
70%
What type of cell can be infected by a bacteriophage?
A bacterial cell
What is a host cell?
A cell infected by a virus
In PCR, each cycle uses the products of the previous cycle as templates. What do you call this?
A chain reaction
What is a DNA library?
A collection of recombinant vectors
What is a cloning vector?
A molecule that carries the DNA to be cloned
What is a virus?
A nonliving particle containing a nucleic acid genome
What is a protobiont?
A precursor to living cells
Which phase of the CRISPR-Cas defense system is depicted in this figure?
Adaptation
Select all that apply Which of the following are examples of base pair mismatches?
Adenine on parent strand and Cytosine on daughter strand Cytosine on parent strand and Thymine on daughter strand Cytosine on parent strand and Adenine on daughter strand
Select all that apply Select functions commonly carried out by ncRNAs.
Alteration of protein function or stability Guide Ribozyme Scaffold Blocker Decoy
Which of these tests is used to evaluate the mutagenicity of an agent?
Ames test
allows a researcher to produce a mutation at a specific sequence.
Blank 1: Site Blank 2: Directed Blank 3: Mutagenesis
This figure best illustrates what type of mutation?
Base substitution
An immune type system in prokaryotes that protects against foreign invaders is called the - system.
Blank 1: CRISPR Blank 2: Cas or Cas9
The enzyme reverse transcriptase synthesizes that is complementary to a viral strand used as a template.
Blank 1: DNA Blank 2: RNA
The genome of a virus can be made of either or
Blank 1: DNA Blank 2: RNA
The DNase I footprinting technique is used to study - interactions.
Blank 1: DNA Blank 2: protein or binding
A researcher may use restriction enzymes to digest the DNA of an organism. The fragments of DNA are then ligated individually into many vectors. This collection of recombinant vectors is called a
Blank 1: DNA or genomic Blank 2: library
ncRNAs that inhibit the integration of TEs into new sites are called - RNAs.
Blank 1: PIWI or p Blank 2: interacting or i
A retrovirus is a virus that has a genome composed of . This type of virus can synthesize DNA through a process called .
Blank 1: RNA Blank 2: reverse Blank 3: transcription
A period on earth when RNA molecules, but not DNA or proteins, were found within protobionts is known as the .
Blank 1: RNA Blank 2: world
PCR allows one to assess the amount of DNA produced during a PCR amplification as it is happening.
Blank 1: Real Blank 2: Time
Some errors affect individual nucleotides and do not distort the DNA double helix. These errors are removed primarily by a DNA repair system called BER, which stands for repair.
Blank 1: base or base excision Blank 2: excision
Mutations in the gene for the RNA component of RNase MRP cause a disorder called - hypoplasia.
Blank 1: cartilage Blank 2: hair
CRISPR stands for , regularly , short, repeats.
Blank 1: clustered Blank 2: interspaced Blank 3: palindromic
The lytic cycle occurs when the activity of the protein exceeds that of the protein.
Blank 1: cro Blank 2: cII or cll
The miR-200 family inhibits an event called the - transition, which is the initiating step of metastasis.
Blank 1: epithelial or E Blank 2: mesenchymal or M
When a human virus is latent its genetic material is either integrated into the host or maintained as an independently replicating genetic element called a(n) .
Blank 1: genome, chromosome, or DNA Blank 2: episome
Cells that give rise to the gametes such as eggs and sperm are called
Blank 1: germ Blank 2: line or cells
The two main mechanisms used to repair DNA double-strand breaks are recombination repair and end joining.
Blank 1: homologous Blank 2: nonhomologous or non-homologous
A cell that harbors a vector is called a
Blank 1: host Blank 2: cell
The viral reproductive cycle results in the production of new viruses by an infected
Blank 1: host Blank 2: cell
The viral reproductive cycle results in the production of new viruses by an infected .
Blank 1: host Blank 2: cell
This figure shows an example of a(n) mutation.
Blank 1: intragenic Blank 2: suppressor
Within HIV particles, the HIV genome is a single-stranded RNA molecule with - repeat sequences at both ends.
Blank 1: long Blank 2: terminal
Alkylating agents covalently attach or groups to DNA bases, and thus disrupt their normal base pairing properties.
Blank 1: methyl or CH3 Blank 2: ethyl, CH2CH3, or CH3CH2
Alkylating agents include nitrogen and ethyl .
Blank 1: mustard Blank 2: methanesulfonate or methane-sulfonate
The probability that a gene will be altered by a new mutation is referred to as the
Blank 1: mutation Blank 2: rate
Some errors create bulky distortions of the double helix. These errors are removed primarily by a DNA repair system called NER, which stands for repair.
Blank 1: nucleotide or nucleotide excision Blank 2: excision
Changes to DNA structure caused by reactive oxygen species (ROS) are termed .
Blank 1: oxidative Blank 2: DNA Blank 3: damage
In 1985, Kary Mullis developed a way to copy DNA without vectors or host cells. This technique is called
Blank 1: polymerase or P Blank 2: chain or C Blank 3: reaction, R, or reactions
During PCR, the process of results when the Taq polymerase catalyzes the synthesis of complementary DNA, starting at the primers.
Blank 1: primer or primer extension Blank 2: extension or extensions
This figure shows a technique known as .
Blank 1: replica Blank 2: plating
The series of steps that occurs involving infection of a host cell, expression of viral genes, and production of new viruses is called the viral .
Blank 1: reproductive Blank 2: cycle
Enzymes that bind to a specific DNA sequence and cut the DNA backbone are called .
Blank 1: restriction Blank 2: endonucleases or enzymes
In order for double-stranded HIV DNA to be incorporated into a host cell chromosome, DNA must be synthesized from an RNA template by the enzyme .
Blank 1: reverse Blank 2: transcriptase
The enzyme that uses RNA as a template to make a complementary strand of DNA is called
Blank 1: reverse Blank 2: transcriptase
Select all that apply Select the two ways that miRNA and siRNA regulate gene expression.
By inducing the binding of RISC which may direct degradation of the mRNA By inducing the binding of RISC which may inhibit translation
Select all that apply Which proteins are able to bind to the operator sequences of OR?
The λ repressor protein The cro protein
Select all that apply Which of the following describe possible structures of the genome of a virus?
Circular Linear
In PCR, the two primers bind to specific sites in the and flank the gene to be amplified.
DNA
In recombination, what is the process that synthesizes small stretches of DNA to replace those removed by strand degradation?
DNA gap repair synthesis
Select all that apply Gene conversion occurs by the action of ______.
DNA gap repair synthesis mismatch repair
This technique enables researchers to determine the DNA bases in genes and other chromosomal regions.
DNA sequencing
Which of the following techniques is used to study protein-DNA interactions?
DNase I footprinting
Which of these represents the correct order of steps during a typical DNA repair system?
Detection → Removal → Replication
Select all that apply What two proteins cleave the pre-miRNA in the nucleus?
Drosha DGCR8
What technique is useful for studying protein-DNA interactions?
Electrophoretic mobility shift assay
Select all that apply Idenfity the diseases that have been associated with abnormalities in heterochromatin formation.
ICF syndrome Roberts syndrome
Select all that apply Select the three phases of the CRISPR-Cas response.
Interference Adaptation Expression
In this figure, two panels are shown. Panel I shows protein A. A first mutation inhibits the function of protein A. In Panel II a second mutation alters protein B to carry out the function of protein A. What is this an example of?
Intergenic suppression
Which scientist developed the polymerase chain reaction?
Kary Mullis
Match each part of the HIV RNA molecule with the correct description.
LTRs matches Choice, Repetitive sequences found at both ends of the RNA U5 and U3 matches Choice, Unique sequences PBS matches Choice, Site for the binding of a primer to initiate DNA synthesis PPT matches Choice, Polypurine tract important for viral DNA synthesis
Select all that apply Which of the following therapies inhibits miRNA function?
Locked nucleic acids Antagomirs
During the assembly of HIV particles, four different domains of the Gag polyprotein bind to different components of the virus or host cell. Match each domain of the Gag polyprotein with its function.
MA matches Choice, Binds to the plasma membrane of the host cell CA matches Choice, Facilitates protein-protein interactions required for viral assembly NC matches Choice, Binds to the HIV RNA genome P6 matches Choice, Binds to Vpr and other proteins that will be contained within the virus particles
Select all that apply What causes abnormal expression levels of ncRNAs, potentially leading to human disease?
Mutations in ncRNA genes Epigenetic changes that alter the expression of ncRNA genes
What protein can stimulate a latent HIV provirus to produce new HIV particles?
NF-κB
Select all that apply Which of these are examples of mutagens?
Nitrous acid Nitrogen mustard 2-Aminopurine 5-Bromouracil
Select all that apply Double-strand breaks are typically repaired by which of the following?
Nonhomologous end joining Homologous recombination repair
This technique is used to identify a specific RNA molecule within a mixture of RNA molecules.
Northern blotting
Because they are expressed in germ-line cells, proteins prevent unwanted TE insertions from being passed from parent to offspring.
PIWI
During the initial stages of a phage λ infection, which two promoters are activated first?
PL and PR
What is a prophage?
Phage DNA integrated into a bacterial chromosome
Which of the following viruses infects bacterial cells and has a genome made of double-stranded DNA?
Phage λ
Select all that apply Which molecular processes will enhance the formation of higher-order structure in heterochromatin?
Posttranslational modifications of histones Binding of proteins to nucleosomes DNA methylation
Select all that apply Which of the following molecules can serve as the genetic material of a virus?
RNA DNA
The signal recognition particle is composed of ______.
RNA and protein
DNA technology uses in vitro molecular techniques that combine DNA fragments to produce novel arrangements.
Recombinant
You have a piece of RNA, and you want to synthesize a complementary strand of DNA. What enzyme would you use?
Reverse transcriptase
Which region in the crRNA is complementary to a strand of bacteriophage DNA?
Spacer
When immature HIV particles are assembled at the plasma membrane of the host cell, what protein binds to the plasma membrane, the HIV RNA, and HIV proteins that will be contained within the viral particles?
The Gag polyprotein
In order for phage λ to enter the lysogenic cycle, what gene must be activated?
The integrase gene
What is recombinant DNA technology?
The production of new arrangements of DNA
When cloning a gene, why must the chromosomal DNA and the plasmid DNA be cut with the same restriction enzyme?
The sticky ends of the plasmid DNA will be complementary to the sticky ends of the chromosomal DNA.
To perform many cycles of PCR, you need a machine that can change temperatures at exact times. What do you call this machine?
Thermocycler
In PCR, why do the primers bind to specific sites in the DNA on either side of the gene of interest?
They are complementary to the flanking sequences.
How did Fire and Mello make the mex-3 antisense strand?
They switched the location of the promoter on the plasmid encoding the mex-3 gene.
What is the purpose of Northern blotting?
To identify a specific RNA molecule within a mixture of RNA molecules
What is the purpose of gene cloning?
To produce many copies of a DNA molecule of interest
Certain compounds have a structure similar to normal DNA bases and so can be incorporated into daughter strands during DNA replication. These compounds are called base
analog
Site-directed mutagenesis allow a researcher to make a mutation ______.
at a specific sequence of DNA
Replica plating is a technique in which ______.
bacterial colonies are transferred from one plate to another with a sterile piece of velvet cloth
A virus that infects bacteria is called a(n)
bacteriophage or phage
Consistent with its role in providing protection against infection, the CRISPR locus contains segments that are derived from DNA.
bacteriophage, phage, or virus
During the normal course of DNA replication, the addition of a nucleotide that does not obey the AT/GC rule of base pairing creates a ______.
base pair mismatch
Base analogs induce mutations by ______.
being incorporated instead of normal bases during DNA replication
miRNAs can act as ______.
both tumor suppressors and oncogenes
The region where two chromosome pieces break and re-attach to other chromosome pieces is called a chromosomal
breakpoint
Nucleotide excision repair (NER) is the main system used in the repair of ______.
bulky, helix distorting lesions
During the initial phase of a real-time PCR experiment, called the phase, the amount of PCR products is small and reagents are not limiting, so the amount of product nearly doubles with each cycle.
exponential
During miRNA processing, a protein called 5 helps to export the pre-miRNA from the nucleus.
exportin
True or false: Since they don't encode proteins, ncRNAs cannot cause disease.
false
True or false: The genome of a virus is always a circular molecule of either DNA or RNA.
false
The inactivation of an X chromosome occurs in ______.
female mammals
When using PCR to amplify DNA, short oligonucleotides called primers ______.
flank the region of DNA to be amplified
Acridine dyes cause ______ mutations.
frameshift
The Ames test assays whether an agent causes ______.
gene mutations
The mutation rate is commonly expressed as the number of new mutations in a given ______.
gene per cell generation
A mutant allele is best defined as an allele that ______.
has a different DNA sequence from the wild-type
The process by which chromosomes exchange similar or identical DNA segments during meiosis is called ______.
homologous recombination
A cell that is infected by a virus is called a(n) cell.
host
What is the term that describes a cell that contains a DNA cloning vector?
host cell
Trinucleotide repeat expansions are repeated sequences of three nucleotide bases which ______.
increase generation after generation
The λ repressor favors lysogeny by _____.
inhibiting expression of genes required for the lytic cycle
Acridine dyes induce mutations by ______.
inserting themselves between adjacent bases and thus distorting DNA structure
When a bacterial cell is infected with phage λ, the phage DNA may integrate into the bacterial chromosome with the aid of an enzyme called .
integrase
What phase of the CRISPR-Cas defense system is depicted in this figure?
interference
The OR region of phage λ DNA acts as a genetic switch between the lysogenic and lytic cycle because its three operator sequences can be bound by either the ______.
repressor protein or the cro protein
DNA gap repair synthesis
restores the stretches of DNA removed by strand degradation at the initiation of recombination.
Genes that encode piRNAs are organized into clusters that contain ______.
several different piRNA sequences separated by sequences that are not complementary to TE RNA
Primer annealing occurs when ______.
short oligonucleotides bind to complementary DNA flanking the gene of interest
Which type of RNA is exogenous?
siRNA
Which type of RNA might originate in a virus?
siRNA
A mutation that does not change the amino acid sequence of a polypeptide is known as a(n) mutation.
silent
The genome of human immunodeficiency virus consists of ______.
single-stranded RNA
Errors in DNA replication are examples of ______ mutations, while mutations caused by ultraviolet light are ______ mutations.
spontaneous ; induced
In PCR, the DNA to be amplified is called the DNA.
template
In PCR, the template DNA is ______.
the DNA to be amplified
The first ncRNA gene shown to be associated with a genetic disease was ______.
the gene encoding the RNA component of RNaseMRP
piRNAs prevent ______.
the integration of transposable elements into new sites
To perform PCR, a machine called a automates the timing of each cycle.
thermocycler
Which of the following proteins inhibits the expression of genes required for the lytic cycle?
λ repressor
Heterochromatic regions found at multiple discrete sites located between the centromeres and telomeres which show with methylated DNA at CpG islands in regulatory regions are called ______ heterochromatin.
facultative
Select all that apply Before replication, a heterochromatic region has sites with fully methylated DNA and nucleosomes with H3K9me3 histone modifications. After DNA replication, what would be the constituents of each daughter chromatid?
half of the H3 histones with H3K9me3 modifications hemimetylated DNA
MicroRNAs influence gene expression by ______.
inhibiting translation of mRNA
In this image, an ncRNA is shown bound to what type of molecule?
mRNA
The methylation of hemimethylated sites is called ______.
maintenance methylation
RNA molecules that do not encode polypeptides are called - RNAs.
non-coding
When there is a gain-of-function mutation in the mouse Agouti gene, the gene is ______ resulting in ______.
over-expressed; yellow fur
Mice that are homozygous for the loss-of-function mutation in the Agouti gene will have black fur because ______.
pheomelanin is not produced
Female honeybee larvae fed and bathed in royal jelly during development will become ______ bees.
queen
In mice, the Agouti gene regulates ______.
the deposition of yellow pigment in hair
n mice, the Agouti gene regulates ______.
the deposition of yellow pigment in hair
Genes that are expressed but do not encode polypeptides produce - RNAs.
Blank 1: non Blank 2: coding
Mello and Fire studied the effects of both and RNA on the expression of mRNAs in C. elegans.
Blank 1: sense Blank 2: antisense
What is the function of the ncRNA HOTAIR?
Scaffold
An RNA that does not encode a polypeptide is a(n) ______ RNA.
non-coding
Mice with a gain-of-function mutation in the Agouti gene will have ______ fur.
yellow
Which of the following represents a higher-order structure found in chromatin?
30-nm fiber
In RNA interference what silences mRNA?
Double-stranded RNA
Select all that apply In eukaryotic cells, which processes are prevented by heterochromatin?
transposable element movement transcription viral proliferation
The process by which some species of plants must be exposed to cold prior to flowering is called
vernalization
Female honeybee larvae fed royal jelly during early development, and nectar or pollen later in development will become ______ bees.
worker
Click and drag on elements in order Put the phases of heterochromatin formation in the correct order, placing the earliest event at the top.
1. nucleation 2. spreading 3. barrier
Click and drag on elements in order List the events of X chromosome inactivation in the correct sequence. putting the first event at the top.
1. x 2. all 3. the tsix 4. list
The phenomenon in which double-stranded RNA causes the silencing of mRNA is called
Blank 1: RNA or RNAi Blank 2: interference or RNAi
During cell division, from M phase in the mother cell to interphase in the resulting two daughter cells, a chromosome will usually retain the same pattern of and heterochromatin that was found in the mother cell.
Blank 1: constitutive Blank 2: facultative
Any assemblage of nucleosomes that assumes a reproducible confirmation in three-dimensional space represents a - structure.
Blank 1: higher or high Blank 2: order
Formation of higher-order structures in heterochromatin depends upon posttranslational modifications of , binding of proteins to , and DNA .
Blank 1: histones Blank 2: nucleosomes Blank 3: methylation
Select all that apply Identify changes that can occur during embryonic development that will lead to a pattern of differential gene expression unique to a specific cell type.
Epigenetic changes that enable specific genes to be transcribed Epigenetic changes that cause specific genes to be permanently repressed
True or false: Because epigenetics refers to heritable changes in gene expression, all epigenetic changes are examples of transgenerational epigenetic inheritance.
False
True or false: Epigenetic changes due to PcG complexes are transient and only present during development.
False
Match the type of chromatin structure with the stage of the cell cycle in which it would be observed.
Interphase matches Choice, Most chromosomal regions are composed of euchromatin. M phase matches Choice, Euchromatic regions condense into constitutive and facultative heterochromatin. M phase through interphase in two daughter cells matches Choice, Constitutive and facultative heterochromatin regions retain the same pattern observed in mother cell.
Select all that apply Why was C. elegans used as the experimental organism in experiments carried out by Mello and Fire?
It is relatively easy to inject with RNA. Expression of many of its genes had already been established.
Select all that apply Which of the following represent key functional roles for heterochromatin in eukaryotic cells?
Preventing viral proliferation Silencing genes Preventing movement of transposable elements
The first macromolecule found in protobionts is thought to be ______.
RNA
Non-coding RNAs are ______.
RNA molecules that do not encode polypeptides
Match the ncRNA with its function.
TERC matches Choice, Facilitates the binding of telomerase to the telomere COLDAIR matches Choice, Alters chromatin structure, repressing transcription CRISPR RNA matches Choice, Guides an endonuclease to foreign DNA PIWI-interacting RNA matches Choice, Prevents the movement of transposable elements
Select all that apply Which of the following statements regarding X inactivation are true?
When the Xist gene is inactive the X chromosome is active Expression of Tsix from both X chromosomes inhibits the expression of Xist In very early embryos, both X chromosomes are active
Epigenetic changes due to the actions of PcG complexes ______.
are maintained in subsequent cell divisions
Which component can prevent heterochromatin spreading into an adjacent euchromatic region of the chromosome?
barrier
Mice that are homozygous for the loss-of-function mutation in the Agouti gene will have ______ fur.
black
Genomic imprinting and X-chromosome inactivation are examples of ______ mechanisms that occur during development.
cis-epigenetic
Vernalization refers to a requirement for ______ before certain plants can undergo flowering.
cold
X chromosome inactivation is an epigenetic event that occurs during ______.
embryogenesis
Multiple tandem repeat sequences near paramutagenic alleles may be involved in paramutation by ______.
producing siRNAs to reduce expression
Select all that apply What are the three ways that PRC1 may inhibit transcription?
Covalent modification of H2A by attraction of ubiquitin molecules Nucleosomes in the target gene may form knot-like structures Direct interaction with transcription factors
Select all that apply Which of the following are features associated with constitutive heterochromatin in yeast and animal cells?
Located at telomeres and close to centromeres DNA is highly methylated on cytosines Composed of many, short tandemly repeated sequences Trimethylation of a lysine at the ninth position in histone H3
The mop1 gene, which is required for paramutation in Arabidopsis, encodes ______ that produces siRNA for gene silencing.
an RNA-dependent RNA polymerase
An area of the chromosome that protects a euchromatic region from spreading of adjacent heterochromatin is called a(n)
barrier
If an epigenetic change is maintained only at a given site and does not affect the expression of a gene elsewhere in the nucleus, it is a ______ mechanism.
cis-epigenetic
A series of genetically programmed stages that begins with sperm and eggs that fuse to become an embryo that will eventually change into an adult is called ______.
development
Select all that apply Select the molecules to which ncRNAs commonly bind.
mRNA Proteins DNA Small molecules
In maize, the dominant allele B-I codes for a transcription factor that regulates genes involved in producing purple color in corn stalks and husks. The allele can undergo a mutation to B' which changes the stalk and husk color from purple to green. In a cross between B-I B-I and B' B' homozygotes, the F1 heterozygotes all have green stalks and husks. When these F1 individuals are crossed to B-I B-I homozygotes, all of the F2 offspring have green stalks and husks. The results for the F2 generation demonstrate a ______ paramutation of the ______ allele.
secondary; B-I allele.
The formation of heterochromatin begins at a site, continues by in both directions, and stops when a site is reached.
Blank 1: nucleation Blank 2: spreading Blank 3: barrier
Select all that apply Which two areas of the X chromosome play a key role in X inactivation?
Tsix Xist
The first step of X inactivation occurs when X chromosomes pair briefly beginning at the ______.
Tsix gene
In mammals, females (XX) and males (XY) express genes on the X chromosome at the same levels because of ______.
X chromosome inactivation
What type of molecules does HOTAIR help guide to their target genes?
Histone-modifying complexes
Select all that apply Which of the following are features associated with facultative heterochromatin?
In animals, contain LINE-type repeated sequences Trimethylation of histone H3 at the 9th or 27th lysine Located at multiple discrete sites between the centromere and telomeres Methylation at CpG islands located in the regulatory regions of genes
Which of the following is an example of epigenetic inheritance?
Methylation of DNA that occurs in an oocyte
Select all that apply Select the roles played by the ncRNA HOTAIR.
Repression of gene transcription Alteration of chromatin structure
Which ncRNA associates with proteins to direct the synthesis of certain polypeptides to the plasma membrane?
SRP RNA
Match each ncRNA function to its correct description.
Scaffold matches Choice, Some ncRNAs contain binding sites for multiple molecules Guide matches Choice, Some ncRNAs function to deliver a molecule to a specific site Ribozyme matches Choice, Some ncRNAs have catalytic function Blocker matches Choice, Some ncRNAs prevent cellular processes from occurring Decoy matches Choice, Some ncRNAs bind to other ncRNAs and sequester them
Which of the following statements regarding X chromosome inactivation is true?
X chromosome inactivation occurs during embryogenesis in females.
Select all that apply Higher-order heterochromatin structure is characterized by ______.
formation of loop domains binding of heterochromatin to the nuclear lamina closer contacts between nucleosomes
A paramutation is a ______.
genetic interaction in which one allele induces a heritable change in the other allele
Select all that apply After vernalization, plants ______.
have the ability to flower when conditions are favorable. have acquired epigenetic modifications in their genome.
The basic repeating unit of chromatin is the , composed of wrapped around an octamer of proteins.
Blank 1: nucleosome Blank 2: DNA Blank 3: histone
Characteristics of higher-order heterochromatin structure include closer contact between , formation of domains and binding of heterochromatin to the nuclear .
Blank 1: nucleosomes Blank 2: loop Blank 3: lamina
In maize, the dominant allele B-I encodes a transcription factor that regulates genes involved in producing purple color of corn stalks and husks. The allele can undergo a mutation to B' which changes the stalk and husk color from purple to green. In a cross between B-I B-I and B' B' homozygotes, the F1 heterozygotes all have green stalks and husks. This shows that the B' allele is and the B-I allele is .
Blank 1: paramutagenic Blank 2: paramutable
Select all that apply Which of the following are true regarding epigenetics?
Variations are reversible from one generation to the next Variations of gene expression are unrelated to variations in the DNA base sequence Epigenetic changes are transmissible from cell to cell Epigenetic changes may be transmitted to offspring
An area of the chromosome that protects a euchromatic region from spreading of adjacent heterochromatin is called a(n) .
barrier
Regions of heterochromatin that are seen in the same location in all cell types are called heterochromatin.
constitutive
Regions of the chromatin containing numerous, short, tandemly repeated sequences that are located near the centromeres and at the telomeres of eukaryotic chromosomes are called ______ heterochromatin.
constitutive
In multicellular species, involves a series of genetically programmed stages in which a fertilized egg becomes an embryo and eventually changes into an adult.
development
MicroRNAs play a key role in regulating gene expression particularly ______.
during embryonic development in animals and plants
ICF syndrome and Roberts syndrome are inherited diseases associated with abnormalities in ______.
heterochromatin formation
A occurs when one allele of a gene induces a heritable change in the other allele without altering the DNA sequence.
paramutation
A heterochromatic region with fully methylated DNA and extensively modified histone H3 prior to DNA replication, will have ______ (the) levels of these modifications in the daughter chromatids produced after DNA replication.
1/2
A precursor to living cells consisting of an aggregate of molecules and macromolecules that acquired a boundary is called a(n) .
protobiont
What happens when pluripotency factors stimulate the expression of Tsix?
Xist is inhibited.
