SB 8

Which are examples of somatic mutations? A mutation in an adult muscle cell A mutation in an egg cell A mutation in an embryonic kidney cell A mutation in a sperm cell

A mutation in an adult muscle cell A mutation in an embryonic kidney cell

Which of the following base changes is a transition mutation? Multiple choice question. A to C A to T C to A C to G A to G

A to G

The mutagen nitrous acid changes cytosine to ___ and adenine to __

Blank 1: uracil Blank 2: hypoxanthine

In trinucleotide repeat expansion disorders, when the expansion occurs in the coding sequence of the gene, the repeat sequence is usually ______. TAG CTG CGG ATG CAG

CAG

Which of the following are small regulatory RNAs? RNAseP RNA COLDAIR CRISPR RNA PIWI-interacting RNA TERC

CRISPR RNA PIWI-interacting RNA

Select the macromolecule that is most versatile. Lipids Proteins DNA RNA

RNA

Which of the following are long non-coding RNAs? Multiple select question. PIWI-Interacting RNA Xist RNA COLDAIR TERC CRISPR RNA

Xist RNA COLDAIR TERC

A base substitution in which a purine and a pyrimidine are interchanged is called a(n) __ mutation

transversion, transverse, transversions, transversive, or transversal

The base cytosine is deaminated to produce the base __

uracil

A missense mutation in the β-globin gene is responsible for sickle cell disease. This mutation causes an altered polypeptide sequence where the sixth amino acid is changed from glutamic acid to ______ valine glutamine phenylalanine aspartic acid

valine

Select the three phases of the CRISPR-Cas response. Adaptation Expression Interference Initiation Termination

Adaptation Expression Interference

An immune type system in prokaryotes that protects against foreign invaders is called the __ __ system

Blank 1: CRISPR Blank 2: Cas or Cas9

During adaptation, what proteins in the CRISPR-Cas system are involved in recognizing and cleaving bacteriophage DNA into small pieces? Cas2 Crispr Cas9 tracr Cas1

Cas2 Cas1

Select the molecules to which ncRNAs commonly bind. DNA mRNA Lipids Small molecules Carbohydrates Proteins

DNA mRNA Small molecules Proteins

Which of the following base changes are transversion mutations? G to C A to C A to G G to A A to T C to T

G to C A to C A to T

Which of the following are forms of tautomers? Acetal Keto Imino Enol Amino

Keto Imino Enol Amino

Following the RNA world, which role did DNA take over from RNA? a) Catalysis of chemical reactions b) Long-term storage of info c) Synthesis of proteins

b) Long-term storage of info

Consistent with its role in providing protection against infection, the CRISPR locus contains segments that are derived from __ DNA

bacteriophage

Nitrous acid is a mutagen that acts via the process of ______. deamination carboxylation demethylation alkylation

deamination

Genetic anticipation refers to what phenomenon? a) An increase in severity of the symptoms as a disease is passed through future generations b) Autosomal recessive disorders that affect only individuals from a specific ethnic group c) Autosomal dominant disorders that affect the individual after reproductive age d) An increase in the number of mutations on a single chromosome over time

An increase in severity of the symptoms as a disease is passed through future generations

Alkylating agents include nitrogen __ and ethyl __

Blank 1: mustard Blank 2: methanesulfonate or methane-sulfonate

Examples of trinucleotide repeat expansion (TRNE) disorders include ___ muscular dystrophy and ___ X syndrome

Blank 1: myotonic, bulbar, or spinal Blank 2: fragile

RNA molecules that do not encode polypeptides are called __-__ RNAs.

Blank 1: non, nc, or n Blank 2: coding, RNA, or c

Select key functions carried out by RNA in an RNA world -The capacity for self-replication -Catalytic function -Ability to form organelles -Ability to serve as a transcript for DNA in the protobiont -The ability to store information in its nucleotide base sequence

-The capacity for self-replication -Catalytic function -The ability to store information in its nucleotide base sequence

What is the length limit that distinguishes long non-coding RNAs from small regulatory RNAs? 1,000 nucleotides 200 nucleotides 25 nucleotides 10,000 nucleotides

200 nucleotides

Which of these are examples of mutagens? Guanine Nitrogen mustard 2-Aminopurine Cytosine Nitrous acid 5-Bromouracil Adenosine triphosphate

Nitrogen mustard 2-Aminopurine Nitrous acid 5-Bromouracil

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. snoRNA tracrRNA piRNA crRNA

crRNA

The removal of an amino group from a base is called

deamination, deaminization, or deaminating

Cells can prevent the buildup of reactive oxygen species by using enzymes such catalase and superoxide __

dismutase

A precursor to living cells consisting of an aggregate of molecules and macromolecules that acquired a boundary is called a(n) ____

protobiont

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

Changes to DNA structure caused by reactive oxygen species (ROS) are termed __ __ __

Blank 1: oxidative Blank 2: DNA Blank 3: damage

An imbalance between the production of reactive oxygen species and an organism's ability to break them down is known as __ __

Blank 1: oxidative Blank 2: stress

the __ __hypothesis states that the resistance of bacteria to T1 infection should arise as a result of exposure to T1 phage but not before.

Blank 1: physiological Blank 2: adaptation

When an ncRNA binds to a(n) __, it can alter its ability to act as a catalyst, or its ability to bind to another molecule.

Blank 1: protein or polypeptide

The ability to make DNA using RNA as a template is called __ __

Blank 1: reverse Blank 2: transcription

During the interference phase, which protein in the CRISPR-Cas system cleaves bacteriophage DNA? Crispr Cas2 Cas9 Cas1 tracr

Cas9

Which of these are used by cells to limit the harmful effects of reactive oxygen species? Catalase Vitamin C Photolyase Superoxide dismutase

Catalase Vitamin C Superoxide dismutase

Which of these are used by cells to limit the harmful effects of reactive oxygen species? Catalase Vitamin C Superoxide dismutase Photolyase

Catalase Vitamin C Superoxide dismutase

Select advantages of having both DNA and RNA in cells versus RNA alone DNA could relieve RNA of its long-term storage role. DNA is more complex than RNA. RNA would be free to perform other functions. DNA is more stable than RNA.

DNA could relieve RNA of its long-term storage role. RNA would be free to perform other functions. DNA is more stable than RNA.

Which ncRNA associates with proteins to direct the synthesis of certain polypeptides to the plasma membrane? snoRNA HOTAIR SRP RNA snRNA

SRP RNA

What new functions would early cells have experienced by the introduction of proteins? Structural roles of proteins Uptake of substances into living cells by membrane proteins Greater self-replicative ability than RNA Greater catalytic ability than RNA

Structural roles of proteins Uptake of substances into living cells by membrane proteins Greater catalytic ability than RNA

Mutations in the 5'-UTR or 3'-UTR of an mRNA molecule are most likely to affect what? The stability of the mRNA The proper splicing of the mRNA The mRNA's ability to be transcribed The mRNA's ability to be translated

The stability of the mRNA The mRNA's ability to be translated

In human cells, what is the ratio of transcription devoted to producing mRNAs vs. ncRNAs?Multiple choice question. a) 20% mRNAs/80% ncRNAs b) 1% mRNAs/99% ncRNAs c) 80% mRNAs/20% ncRNAs d) 50% mRNAs/50% ncRNAs e) 99% mRNAs/1% ncRNAs

a) 20% mRNAs/80% ncRNAs

Because a bacterial cell must first be exposed to an agent to elicit a response, the CRISPR-Cas system is called a(n) ______. a) adaptive defense system b) acute defense system c) interference defense system d) prolonged defense system

a) adaptive defense system

The covalent bond between deoxyribose and a purine base is rather unstable and can undergo a spontaneous reaction with water. The breaking of the bond releases the base, and leaves a(n) ___ site in the DNA

apurininc

Replica plating is a technique in which ______. a) bacterial colonies are transferred from one plate to another with a sterile piece of velvet cloth c) bacteria are grown in broth then allowed to replicate to produce colonies d) bacterial colonies are transferred from one plate to another with a sterile glass pipette

bacterial colonies are transferred from one plate to another with a sterile piece of velvet cloth

CRISPR-Cas systems provide a defense against ______. . bacteriophages plasmids bacteria transposons

bacteriophages plasmids transposons

CRISPR stands for

clustered, regularly interspaced, short, palindromic repeats

Alkylating agents cause mutations by ______. creating thymine dimers that block DNA replication being incorporated instead of normal bases during DNA replication forming free radicals that damage DNA structure disrupting the normal pairing between nucleotides within the DNA

disrupting the normal pairing between nucleotides within the DNA

A position effect can alter gene expression in cases when the gene is moved from a less condensed, or ______ chromosome, where it is active, to a very highly condensed, or ______ chromosome, where its expression may be turned off. heterochromatic ; homochromatic euchromatic ; aneuchromatic euchromatic ; heterochromatic heterochromatic ; euchromatic

euchromatic ; heterochromatic

True or false: In human cells, mRNAs are more abundant than ncRNAs.

false

A mutation that occurs directly in a sperm or egg cell, or in one of their precursor cells, is referred to as a(n) __ __ mutation

germ-line

Proteins associated with trinucleotide repeat expansion disorders typically contain long tracts of the amino acid ___

glutamine

Of the four bases normally found in DNA, ___ is most vulnerable to oxidation.

guanine, guanosine, or G

A trinucleotide repeat expansion commonly occurs via the formation of a(n) ______. DNA intermediate that enhances transcription tautomeric shift that interferes with DNA replication reactive oxygen species that changes DNA structure hairpin that interferes with DNA replication

hairpin that interferes with DNA replication

If an individual possesses a germ-line mutation, then ______ produced by the individual will carry the mutation. If an individual possesses a somatic mutation, then ______ produced by the individual will carry the mutation. none of the gametes ; half of the gametes half of the gametes ; all of the gametes half of the gametes ; none of the gamete sall of the gametes ; half of the gametes all of the gametes ; none of the gametes

half of the gametes ; none of the gametes

A genetic mosaic is an individual that ______. has more chromosomes than the wild-type number is the result of germ-line mutations in both parents has regions of the body that are genotypically different from each other is a hybrid between two genotypically similar individuals

has regions of the body that are genotypically different from each other

For a tautomeric shift to cause a mutation, it must occur ______. immediately prior to DNA replication at any time during the cell cycle immediately following DNA replication immediately following transcription

immediately prior to DNA replication

Proflavin is best described as a(n) ______ agent. reductive oxidative alkylating intercalating

intercalating

The common stable form of guanine and thymine is the ______ form. Multiple choice question. imino amino enol keto

ket

An individual that has one copy of the sickle cell allele and one copy of the wild-type allele has an increased level of resistance to the disease __

malaria

Nitrous acid causes mutations by ______. creating thymine dimers that block DNA replication forming free radicals that damage DNA structure acting as a base analog during DNA replication modifying bases and thus altering their normal base-pairing properties

modifying bases and thus altering their normal base-pairing properties

Guanine is commonly ______. oxidized to 5-oxoguanine oxidized to 8-oxoguanine reduced to 5-hydroxyguanine reduced to 8-hydroxyguanine

oxidized to 8-oxoguanine

The expression of an intact gene may be altered when it is moved to a new location. This is due to a(n) ______. position effect X-inactivation breakpoint effect tautomeric shift

position effect

Reactive oxygen species (ROS) are ______. organisms that have adverse reactions when grown in oxygen products of oxygen metabolism in all aerobic organisms products of metabolism in the absence of oxygen organisms that can only grow in the presence of oxygen

products of oxygen metabolism in all aerobic organisms

The CRISPR locus in prokaryotes contains a series of ______. intron-rich sequences repeated sequences function-less sequences ribosomal RNA sequences

repeated sequences

ncRNAs that contain binding sites for multiple components can act as a(n) ___ for the formation of a complex.

scaffold

Trinucleotide repeats can form hairpins due to ______. non-homologous end joining sloppy DNA polymerases spontaneous nucleotide excision repair slipped mispairing during DNA replication

slipped mispairing during DNA replication

If the patch of white hair in this child were larger, that would indicate a ______ mutation that occurred ______ during embryonic development. germ-line; earlier germ-line; later somatic; earlier somatic; later

somatic; earlier

Mutations in eukaryotic genes that change the __ recognition sequences may affect the order and/or number of exons contained in the mature mRNA.

splice or splicing

A change of one base for another is described as a base __ mutation

substitution or point

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

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? Position effect Intergenic suppression Intragenic suppression Breakpoint effect

Intergenic suppression

Select functions commonly carried out by ncRNAs. Scaffold Guide Alteration of protein function or stability Decoy Component of cell membrane Assembly of organelles Blocker Ribozyme

Scaffold Guide Alteration of protein function or stability Decoy Blocker Ribozyme

Trinucleotide repeat expansions are repeated sequences of three nucleotide bases which ______. are used as templates to repair damaged DNA are associated with various cancers increase in number via reciprocal translocations increase generation after generation

increase generation after generation

An intergenic suppressor mutation may involve which of the following? A change in the expression of one gene that compensates for the loss-of-function mutation in another gene A gain-of-function mutation in one gene that compensates for the loss-of-function mutation in the same gene A change in protein structure that compensates for an abnormality in protein structure caused by the first mutation

A change in the expression of one gene that compensates for the loss-of-function mutation in another gene

What is the effect of a suppressor mutation? It suppresses the activity of a cytoplasmic protein. It suppresses the division of a prokaryotic cell. It suppresses the expression of a eukaryotic gene. It suppresses the phenotypic effect of another mutation.

It suppresses the phenotypic effect of another mutation.

A second mutation that occurs in a different site than the first mutation, and which converts the mutant back to the wild-type phenotype, is best referred to as a(n) __ mutation

suppressor

Select ways in which the binding of an ncRNA to a protein may affect the protein's function. It may affect the sequence of the protein. It may affect the stability of the protein. It may affect the ability of the protein to act as a catalyst. It may affect the ability of the protein to bind another molecule.

It may affect the stability of the protein. It may affect the ability of the protein to act as a catalyst. It may affect the ability of the protein to bind another molecule

A temporary change in base structure due to movement of hydrogen atoms is called a(n)

tautomeric shift

In which of the following ways does 5-bromouracil cause a mutation? It replaces the base thymine, and can base pair with guanine rather than adenine. It replaces the base cytosine, and can base pair with thymine rather than guanine. It replaces the base cytosine, and can base pair with adenine rather than guanine. It replaces the base thymine, and can base pair with cytosine rather than adenine.

It replaces the base thymine, and can base pair with guanine rather than adenine.

Bases which exist in keto and enol or amino and imino forms are best described as ______. Multiple choice question. diasteriomers topoisomers tautomers enantiomers

tautomers

A(n) ___ is a type of base substitution that involves a change of a pyrimidine to another pyrimidine, or a purine to another purine.

transition or transitions

Order the genes commonly found in the CRISPR-Cas type II system. Start with tracr at the top. tracr, Crispr, Cas1, Cas2, Cas9

tracr Cas9 Cas1 Cas2 Crispr

Which of the following statements about promoter mutations is true? Down promoter mutations occur in the 3'-UTR of the gene Up promoter mutations occur in the coding sequence of the gene 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

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

The oxidized form of guanine, 8-oxoguanine, can produce a _____ mutation. inversion frame-shift transversion transition

transversion

Select features that make protobionts possible precursors of living cells Protobionts contained DNA. Protobionts developed the capability of self-replication. Polymers inside the protobiont had catalytic functions. Polymers inside the protobiont contained information. A boundary separated the internal contents of the protobiont from the external environment. Protobionts contained polymers organized into organelles.

Protobionts developed the capability of self-replication. Polymers inside the protobiont had catalytic functions. Polymers inside the protobiont contained information. A boundary separated the internal contents of the protobiont from the external environment.

In modern cells, how does RNA function in protein synthesis? Ribosomes containing rRNA provide a site for polypeptide synthesis. A ribosomal RNA (rRNA) acts as a ribozyme to catalyze peptide bond formation. Guide RNAs are used to bring messenger RNAs to the ribosome. Non-coding RNAs are essential in linking amino acids together to form a polypeptide. Transfer RNA (tRNA) molecules act as adaptors for polypeptide formation. Messenger RNA (mRNA) provides information for producing the sequence of a polypeptide.

Ribosomes containing rRNA provide a site for polypeptide synthesis. A ribosomal RNA (rRNA) acts as a ribozyme to catalyze peptide bond formation. Transfer RNA (tRNA) molecules act as adaptors for polypeptide formation. Messenger RNA (mRNA) provides information for producing the sequence of a a polypeptide.

Rank these molecules according to catalytic activity, placing the molecule with the greatest catalytic ability on top. DNA, RNA, Proteins

Proteins RNA DNA

Acridine dyes induce mutations by ______. a) inserting themselves between adjacent bases and thus distorting DNA structure b) forming reactive oxygen species that damage DNA structure c) creating thymine dimers that block DNA replication d) disrupting the normal pairing between nucleotides within the DNA

a) inserting themselves between adjacent bases and thus distorting DNA structure

Reactive oxygen species (ROS) are ______. organisms that can only grow in the presence of oxygen organisms that have adverse reactions when grown in oxygen products of metabolism in the absence of oxygen products of oxygen metabolism in all aerobic organisms

products of oxygen metabolism in all aerobic organisms

Assume a tautomeric shift occurred, which was followed by two rounds of DNA replication. If the mutation is not repaired, what would be the result? GC to AT mutation in all of the four daughter molecules GC to AT mutation in two of the four daughter molecules AT to GC mutation in two of the four daughter molecules AT to GC mutation in all four of the daughter molecules AT to GC mutation in one of the four daughter molecules

AT to GC mutation in one of the four daughter molecules

TERC, COLDAIR, CRISPR RNA, PIQI-interacting RNA Alters chromatin structure, repressing transcription Prevents the movement of transposable elements Guides an endonuclease to foreign DNA Facilitates the binding of telomerase to the telomere

TERC= Facilitates the binding of telomerase to the telomere COLDAIR= Alters chromatin structure, repressing transcription CRISPR RNA= Guides an endonuclease to foreign DNA PIWI-interacting RNA= Prevents the movement of transposable elements

Which of the following bases is produced by the deamination of 5-methylcytosine? Adenine Cytosine Thymine Guanine

Thymine

Which of these are trinucleotide repeat expansion disorders? Huntington disease Fragile X syndrome Marfan syndrome Duchenne muscular dystrophy Myotonic muscular dystrophy

Huntington disease Fragile X syndrome Myotonic muscular dystrophy

The amino form is the common stable form of which bases? Multiple select question. Cytosine Guanine Thymine Adenine

Cytosine Adenine

The restoration of function by a second mutation at a different site in the same gene is known as a(n) ______. tautomeric shift intergenic suppressor intragenic suppressor position effect

intragenic suppressor

Which of these bases is most readily deaminated? Guanine Adenine Cytosine Thymine

Cytosine

A mutation that results in a premature termination of the synthesis of a polypeptide is called a(n)

nonsense mutation