Genetics test 2

Which of the following is NOT a characteristic of the genetic

material?

It must be capable of change.

It must be replicated accurately.

It contains all the information needed for growth, development, and reproduction of the organism.

It is composed of protein.

It is composed of protein.

Considering the structure of double-stranded DNA, which kind(s) of bonds hold one complementary strand to the

other?

ionic

van der Waals

disulfide

covalent

hydrogen

hydrogen

Spleen diesterase is an enzyme that breaks the covalent bond that connects the phosphate to the 5' carbon. If the dinucleotide is digested with spleen diesterase, to which base and to which carbon on the sugar is the phosphate now attached?

T; 5'

A; 5'

T; 3'

A; 3'

A; 3'

The covalent linkage between the monomers in a dinucleotide is a(n) ________.

ester bond

peptide bond

phosphodiester bond

disulfide bond

ionic bond

phosphodiester bond

(showing a RNA molecule) If this molecule were found in a DNA chain, the chemical group labeled (X) would be ________ and the chemical group labeled (Y) would be

________.

H; OH

H; H

OH; OH

OH; H

OH; H

Guanine and adenine are purines found in DNA.

True

False

true

Which of the following statements about DNA structure is

true?

Hydrogen bonds formed between the sugar-phosphate backbones of the two DNA chains help to stabilize DNA structure.

The nucleic acid strands in a DNA molecule are oriented antiparallel to each other, meaning they run in opposite directions.

The pentose sugar in DNA is ribose.

Nucleic acids are formed through phosphodiester bonds that link nucleosides together.

The nucleic acid strands in a DNA molecule are oriented antiparallel to each other, meaning they run in opposite directions.

What is the complementary DNA sequence to 5' ATGCTTGACTG

3'?

5' ACTCTACGTAG 3'

5' ATGCTTGACTG 3'

5' TACGAACTGAC 3'

5' CAGTCAAGCAT 3'

5' CAGTCAAGCAT 3'

The base content of a sample of nucleic acid is as follows: A = 31%, G = 31%, T = 19%, C = 19%. What conclusion should be drawn from this information?

This nucleic acid is single-stranded DNA.

This nucleic acid is made of RNA.

The purine/pyrimidine ratio in this molecule fits Chargaff's data.

The strands in this molecule are parallel rather than antiparallel.

This nucleic acid is double-stranded DNA.

This nucleic acid is single-stranded DNA.

Which of the following statements about the basic structural features of DNA are true?

Select all true statements.

The twisting of the DNA double helix is attributed to the tight packing of DNA bases and base-stacking.

The major and minor grooves form in the DNA helix because the DNA strands are antiparallel.

The major and minor grooves prevent DNA binding proteins from making contact with nucleotides.

In a DNA macromolecule, the two strands are complementary and antiparallel.

The twisting of the DNA double helix is attributed to the tight packing of DNA bases and base-stacking.

In a DNA macromolecule, the two strands are complementary and antiparallel.

Consider the following two statements about DNA melting temperature:

1)The melting temperature of a sample of DNA is the temperature at which 50% of the double

helices in the sample have completely denatured.

2)A molecule with 53% GC base pairs would have a higher melting temperature than a molecule

of equivalent length with 53% AT base pairs.

Determine which one of the statements below is

correct.

Statement 1) is true; statement 2) is false.

Statement 1) is false; statement 2) is true.

Statement 1) and statement 2) are false.

Statement 1) and statement 2) are true.

Statement 1) is false; statement 2) is true.

Explain the technique of electrophoretic separation of DNA fragments.

A mixture of different sized DNA molecules are subjected to an electric field, and then to a magnetic field. The fragments migrate through a liquid matrix such that smaller fragments travel further in the matrix.

A mixture of different sized DNA molecules are subjected to an electric field, and migrate through a semisolid matrix such that smaller fragments travel further in the matrix.

A mixture of different sized DNA molecules are subjected to an electric field, and migrate through a solid matrix such that larger fragments travel further in the matrix.

A mixture of different sized DNA molecules are subjected to an electric field, and then to a magnetic field. The fragments migrate through a semisolid matrix such that larger fragments travel further in the matrix.

A mixture of different sized DNA molecules are subjected to an electric field, and migrate through a semisolid matrix such that smaller fragments travel further in the matrix.

List three main differences between DNA and RNA.

Check all that apply.

Uracil in RNA replaces thymine in DNA.

Ribose in RNA replaces deoxyribose in DNA.

Ribose in RNA replaces thymine in DNA.

RNA often occurs as both single- and partially double-stranded forms, whereas DNA most often occurs in a double- stranded form.

DNA often occurs as both single- and partially double-stranded forms, whereas RNA most often occurs in a double- stranded form.

Uracil in RNA replaces deoxyribose in DNA.

Uracil in RNA replaces thymine in DNA.

Ribose in RNA replaces deoxyribose in DNA.

RNA often occurs as both single- and partially double-stranded forms, whereas DNA most often occurs in a double- stranded form.

Which terms accurately reflect the nature of replication of the chromosome in E. coli?

bidirectional and fixed point of initiation

unidirectional and reciprocal

unidirectional and fixed point of initiation

multirepliconic and telomeric

bidirectional and multirepliconic

bidirectional and fixed point of initiation

Is there any role for an RNA polymerase in DNA replication?

No, only DNA polymerases function in DNA replication

Yes, in order to synthesize mRNA

Yes, to generate primers

Yes, to synthesize RNA that will bind to and keep the two DNA strands unwound

Yes, in eukaryotes an RNA polymerase functions in telomere maintenance

Yes, to generate primers

The role of the DnaA protein in bacterial DNA replication is to:

prevent renaturation of the two DNA strands during replication

synthesize an RNA primer

relieve the tension of supercoiling

unwind the double helix

detect replication errors

unwind the double helix

Given that the origin of replication is fixed in E. coli, what signals the location of the origin?

A region called oriC, which consists of about 250 base pairs characterized by repeating sequences of 9 and 13 bases

During DNA replication, what is the function of RNA primase?

it provides a free 3′-OH upon which DNA polymerization depends

it is involved in preventing the leading strand from replicating too quickly.

it prevents DNA from reannealing to itself during the replication process (i.e., it keeps the DNA single-stranded).

it allows trascription to proceed while DNA replication is occurring.

it provides secondary structure to the replisome to maintain replication stability.

it provides a free 3′-OH upon which DNA polymerization depends

Which cluster of terms accurately reflects the nature of DNA replication in prokaryotes?

fixed point of initiation, bidirectional, conservative

fixed point of initiation, unidirectional, conservative

random point of initiation, bidirectional, semiconservative

fixed point of initiation, bidirectional, semiconservative

random point of initiation, unidirectional, semiconservative

fixed point of initiation, bidirectional, semiconservative

The discontinuous aspect of replication of DNA in vivo is caused by ________.

polymerase slippage

trinucleotide repeats

the 5′ to 3′ polarity restriction

topoisomerases cutting the DNA in a random fashion

sister-chromatid exchanges

the 5′ to 3′ polarity restriction

DNA polymerase III adds nucleotides ________.

to the 3′ end of the RNA primer

to the 5′ end of the RNA primer

in the place of the primer RNA after it is removed

to both ends of the RNA primer

to internal sites in the DNA template

to the 3′ end of the RNA primer

DNA polymerase I is thought to add nucleotides ________.

to the 5′ end of the primer

to the 3′ end of the primer

in the place of the primer RNA after it is removed

on single-stranded templates without need for an RNA primer

in a 5′ to 5′ direction

in the place of the primer RNA after it is removed

Telomerase _____.

contains its own RNA template

extends one strand of the telomere

is responsible for helping to maintain chromosome size

is found primarily in bacteria

contains its own RNA template

extends one strand of the telomere

is responsible for helping to maintain chromosome size

Any molecule that serves as the genetic material must have the following characteristics except _____.

the ability to be replicated

the ability to store information

the ability to directly influence the development of traits

the ability to express information

the potential to be changed via mutation

the ability to directly influence the development of traits

Which of the following is not a key property of heredity material?

It must be capable of being copied accurately

It must encode the information necessary to form proteins and complex structures

It must occasionally mutate

It must be able to adapt itself to each of the body's tissues

It must effectively store and transmit information

It must be able to adapt itself to each of the body's tissues

Which of the following are purines?

Adenine

Cytosine

Guanine

thymine

Adenine and guanine

Which of the following is an example of a nucleobase?

Adenine

Adenosine

Deoxyadenosine

Deoxyadenosine monophosphate

Deoxyadenosine diphosphate

Deoxyadenosine triphosphate

Adenine

How many phosphate atoms are present in each subunit of single stranded DNA?

1

2

3

4

5

1

A nucleic acid was analyzed and found to contain 32% A, 25% C, 21% G, and 22% T. This sample came from:

Single-stranded DNA

Single-stranded RNA

Double-stranded DNA

Double-stranded RNA

Single-stranded DNA

The percent of adenine in a sample of double stranded DNA is 21%. What is the percent of cytosine in that DNA (leave the % off your answer)?

29

Which of the following does not describe a bond found in a DNA double helix.

Phosphodiester

Covalent

Hydrogen

Intramolecular

Peptide

Peptide

Pick the best answer. DNA is a polymer of what subunit:

Nucleosides

Fatty acids

Deoxyribose sugars

Nucleotides

Triphosphates

Deoxyribose sugars

Nucleotides

Which of the following is not consistent with Erwin Chargaff's findings?

(A + G) = (C + T)

(A + C) = (G + T)

A = T

(C + G) = (A + T)

(A + G) / (C + T) = 1

(C + G) = (A + T)

Explain the technique of electrophoretic separation of DNA fragments.

A mixture of different sized DNA molecules are subjected to an electric field, and migrate through a semisolid matrix such that smaller fragments travel further in the matrix.

Which statement is true?

The fewer hydrogen bonds between bases, the higher the temperature needed to separate the pair.

The more hydrogen bonds between bases, the higher the temperature needed to separate the pair.

The more hydrogen bonds between bases, the higher the temperature needed to separate the pair.

Which statement is true?

G-C base pairs have three hydrogen bonds while A-T base pairs have two hydrogen bonds.

A-T base pairs have three hydrogen bonds while G-C base pairs have two hydrogen bonds.

G-C base pairs have three hydrogen bonds while A-T base pairs have two hydrogen bonds.

Without DNA gyrase ??? induced by ??? the tension in the closed circle of DNA would cause replication machinery to stall preventing the cells from dividing.

supercoiling DNA helicase

During DNA replication, an open section of DNA, in which a DNA polymerase can replicate DNA, is called a

replication fork

The new DNA strand that grows continuously in the 5' to 3' direction is called the

leading strand

After replication is complete, the strand of new DNA is complementary to the parental strand and its called what

daughter DNA

The enzyme that can replicate DNA is called

DNA polymerase

??? are the short sections of DNA that are synthesized on the lagging strand of the replicating DNA

Okazaki Fragments

direction RNA/DNA is syntesized

5' to 3'

The synthesis of a new DNA strand along the template is performed by

Dna polymerase

The role of the ??? is to ensure that the enzyme creating the new DNA strands does not become unattached from the template strand.

sliding DNA clamp subunit

To prevent knotting of the template DNA as the replication fork moves,

??? makes temporary nicks in the template DNA.

DNA gyrase

The replication fork contains template DNA strands that were recently separated by ??? to become single stranded.

DNA helicase

To ensure that single strands near the replication fork do not reanneal to each other, ??? attach to template strands.

single stranded binding proteins

Which statement best describes the direction of DNA polymerase during DNA replication?

DNA polymerase synthesizes in the 5′ to 3′ direction on both the leading and lagging strands.

DNA polymerase synthesizes in the 3′ to 5′ direction on both the leading and lagging strands.

DNA polymerase synthesizes in the 5′ to 3′ direction on the lagging strand only.

DNA polymerase synthesizes in the 5′ to 3′ direction on the leading strand only

DNA polymerase synthesizes in the 5′ to 3′ direction on both the leading and lagging strands.

Where are Okazaki fragments formed during DNA

replication?

Okazaki fragments are formed on the lagging strand.

Okazaki fragments are formed on the leading strand.

Okazaki fragments are formed on both the leading and lagging strands.

Okazaki fragments are formed just ahead of the replication fork where DNA is still double-stranded.

Okazaki fragments are formed on the lagging strand.

Suppose you're working in a lab that creates a mutant cell line in which DNA replication is impaired. Upon sequencing, you discover a loss-of-function mutation associated with single-stranded binding proteins. Based on that limited information, what problem might you suspect is occurring at the molecular

level?

DNA polymerase does not synthesize in the correct direction.

The replication fork is not stabilized and collapses before DNA polymerase can complete a new strand.

The Okazaki fragments do not join together properly on the lagging strand.

The DNA template never becomes single stranded at the replication fork.

The replication fork is not stabilized and collapses before DNA polymerase can complete a new strand.

Protein that breaks H bond

DNA helicase

Proteins that form or break covalent bonds

DNA poly 1

DNA poly 2

DNA gyrase

DNA ligase

primase

how do telomeres terminate

5'TTGGGG3'

what is telomerase purpose and why

create repeating sequences to decrease likely hood of shortening of important genes

Which structures can be involved in recombination?

Any two chromosomes

Chromatids of nonhomologous chromosomes

Chromosomes in different cells

Chromatids of homologous chromosomes

Chromatids of homologous chromosomes

The process that determines the length of heteroduplex DNA on the chromatids is called branch migration.

True

False

True

Which process does not occur during recombination?

Ligation

Nicking of the sugar‑phosphate backbone

Strand displacement

DNA polymerization

DNA polymerization

Identify the properties of DNA polymerase I. Select all that

apply.

elongates existing DNA strands

polymerizes nucleotides from 5' to 3'

removes RNA primer

3' to 5' exonuclease activity

5' to 3' exonuclease activity

all

Identify the properties of DNA polymerase II. Select all that

apply.

elongates existing DNA strands

polymerizes nucleotides from 5' to 3'

removes RNA primer

3' to 5' exonuclease activity

5' to 3' exonuclease activity

elongates existing DNA strands

polymerizes nucleotides from 5' to 3'

3' to 5' exonuclease activity

Identify the properties of DNA polymerase III. Select all that

apply.

elongates existing DNA strands

polymerizes nucleotides from 5' to 3'

removes RNA primer

3' to 5' exonuclease activity

5' to 3' exonuclease activity

elongates existing DNA strands

polymerizes nucleotides from 5' to 3'

3' to 5' exonuclease activity

Why is DNA synthesis expected to be more complex in eukaryotes than in bacteria?

Check all that apply.

Eukaryotic cells contain much more DNA.

DNA replication in eukaryotes is known to proceed with much more fidelity than in bacteria.

In eukaryotic cells, DNA is complexed with histones.

There is a high occurrence of regions with unusual DNA structure in eukaryotic chromosomes.

Eukaryotic chromosomes are linear rather than circular.

There are fewer DNA polymerase molecules per cell in eukaryotes compared to bacteria.

Eukaryotic cells contain much more DNA.

In eukaryotic cells, DNA is complexed with histones.

Eukaryotic chromosomes are linear rather than circular.

How is DNA synthesis similar in the two types of organisms?

Check all that apply.

Synthesis is accompanied with disruption and reassembly of nucleosomes.

Synthesis proceeds from multiple replication origins.

Synthesis requires the template, primer and the same set of raw molecular species.

Synthesis is bidirectional.

Synthesis involves the action of telomerase enzyme.

Synthesis is continuous on one strand and discontinuous on the other.

Synthesis requires the template, primer and the same set of raw molecular species.

Synthesis is bidirectional.

Synthesis is continuous on one strand and discontinuous on the other.

Mutant (a):

Newly synthesized DNA contains many mismatched base pairs.

What enzyme or function is being affected in Mutant (a), causing many mismatched base pairs?

no DNA gyrase activity

no Primase activity

no DNA ligase activity

only DNA polymerase I activity

no DNA repair

no DNA repair

Mutant (b):

Okazaki fragments accumulate, and DNA synthesis is never completed.

What enzyme or function is being affected in Mutant (b), causing the accumulation of Okazaki fragments and failure to complete DNA

synthesis?

no DNA repair

only DNA polymerase I activity

no DNA ligase activity

no DNA gyrase activity

no Primase activity

no DNA ligase activity

Mutant (c):

No initiation occurs.

What enzyme or function is being affected in Mutant (c), causing DNA synthesis to never be

initiated?

no DNA gyrase activity

no DNA repair

no DNA ligase activity

no Primase activity

only DNA polymerase I activity

no Primase activity

Mutant (d):

Synthesis is very slow.

What enzyme or function is being affected in Mutant (d), causing DNA synthesis to be very

slow?

no Primase activity

no DNA ligase activity

no DNA gyrase activity

only DNA polymerase I activity

no DNA repair

only DNA polymerase I activity

Mutant (e):

Supercoiled strands remain after replication, which is never completed.

What enzyme or function is being affected in Mutant (e), causing supercoiled DNA to remain after

replication?

no Primase activity

no DNA ligase activity

only DNA polymerase I activity

no DNA repair

no DNA gyrase activity

no DNA gyrase activity

DNA polymerases in all organisms add only 5′ nucleotides to the 3′ end of a growing DNA strand, never to the 5′ end. -why

One possible reason for this is the fact that most DNA polymerases have a proofreading function that would not be energetically possible if DNA synthesis occurred in the 3′ to 5′ direction.

Consider the information in your sketch and speculate as to why proofreading would be

problematic.

If DNA polymerase removed a base, it would not be able to add any more bases to the chain because the penultimate base would have a diphosphate rather than a triphosphate, and there would be no source of energy for the polymerization reaction.

If DNA polymerase removed a base, it would not be able to add any more bases to the chain because the penultimate base would have a triphosphate rather than a monophosphate, and there would be no source of energy for the polymerization reaction.

If DNA polymerase removed a base, it would not be able to add any more bases to the chain because the penultimate base would have a monophosphate rather than a triphosphate, and there would be no source of energy for the polymerization reaction.

If DNA polymerase removed a base, it would not be able to add any more bases to the chain because the penultimate base would have a monophosphate rather than a triphosphate, and there would be no source of energy for the polymerization reaction.

Chromosomal regions that represent evolutionary vestiges of duplicated copies of genes that have underdone sufficient mutations to render them untranscribable are called

________.

transposons

LINEs

pseudogenes

alleles

satellites

pseudogenes

SINE =

LINE =

These structures are called repetitive because they contain multiple copies of

short interspersed elements

long interspersed elements

identical sequences

Chromatin of eukaryotes is organized into repeating interactions with protein octomers called nucleosomes. Nucleosomes are composed of which class of

molecules?

nonhistone chromosomal proteins

lipids

H1 histones

glycoproteins

histones

histones

In addition to highly repetitive and unique DNA sequences, a third category of DNA sequences exists. What is it called, and what types of elements are involved in

it?

dominant DNA; euchromatin and heterochromatin

multiple gene family DNA; hemoglobin and 5.0S RNA

composite DNA; telomeres and heterochromatin

moderately repetitive DNA; SINEs, LINEs, and VNTRs

permissive DNA; centromeres and heterochromatin

moderately repetitive DNA; SINEs, LINEs, and VNTRs

Nucleosomes are composed of ???

different histone molecules, each of which exists ???

thus forming a(n) ???

Histone H1 is ???

and is associated with ???

four

twice

octet

in between nucleosomes

linker DNA

What are minisatellites and

microsatellites?

Both are sequences representing evolutionary vestiges of duplicated copies of genes that have undergone significant mutational alteration.

Both are highly repetitive, relatively short DNA sequences.

Both are relatively short mobile sequences that can potentially move to different locations within the genome.

Both are condensed parts of chromosomes, but microsatellites are shorter than minisatellites.

Both are highly repetitive, relatively short DNA sequences.

Approximately how much of the mammalian genome is composed of repetitive

DNA?

About 30-40% of a mammalian genome is highly repetitive; about 70% is moderately repetitive.

About 5-10% of a mammalian genome is highly repetitive; about 30% is moderately repetitive.

About 70% of a mammalian genome is highly repetitive.

About 1% of a mammalian genome is highly repetitive; about 5% is moderately repetitive.

About 5-10% of a mammalian genome is highly repetitive; about 30% is moderately repetitive.

Which histone helps stabilize the solenoid

structure?

H1

H2A

H2B

H3

H4

H1

Histone acetyltransferases are capable of remodeling chromatin by adding acetyl groups to various lysine residues in histones that comprise the nucleosome. Following this modification, the lysine residue no longer has a positive charge. Which statement is

true?

Histones have a net positive charge that allow them to bind to DNA. Acetylation of histones, decreases their positive charge and weakens the histone-DNA interaction

Histones have a net positive charge that allow them to bind to DNA. Acetylation of histones, decreases their positive charge and strengthens the histone-DNA interaction

Histones have a net negative charge that allow them to bind to DNA. Acetylation of histones, decreases their positive charge and strengthens the histone-DNA interaction

Histones have a net negative charge that allow them to bind to DNA. Acetylation of histones, decreases their positive charge and weakens the histone-DNA interaction

Histones have a net positive charge that allow them to bind to DNA. Acetylation of histones, decreases their positive charge and weakens the histone-DNA interaction.

Euchromatin vs Heterochromatin

Heterochromatic regions of chromosomes are relatively inaccessible to transcriptional proteins either transiently (in the case of facultative heterochromatin) or nearly always (in the case of constitutive heterochromatin).

bullet

In contrast, in euchromatic chromosome regions, transcriptional proteins and enzymes are more easily able to gain access to DNA.

Which of the following are examples of heterochromatin?

Select all that apply.

centromeric DNA

telomeric DNA

Barr body

repetitive DNA

centromeric DNA

telomeric DNA

Barr body

repetitive DNA

sort these into satellite DNA, tandem repeats, and Transposable Sequences

LINEs

STRs

heterochromatic centromeric regions

VNTRs

SINEs

satellite DNA-heterochromatic centromeric regions

tandem repeats-VNTRs and STRs

Transposable Sequences-LINEs and SINEs

t/f The number VNTRs of each specific sequence at each location varies from one individual to the next.

true

t/f The number of STRs present at any site are highly conserved between individuals.

false

Alu elements are SINEs that typically encode an important human t/f protein, the restriction endonuclease Alu I.

false

t/f The most prominent example of LINEs in humans are L1 elements.

true

t/f The human genome contains mobile genetic elements called retrotransposons that encode reverse transcriptase to catalyze transposition.

true

Why might we predict that the organization of eukaryotic genetic material will be more complex than that of viruses or

bacteria?

Genomic size always increases with organismic complexity.

Eukaryotes have large amounts of extra (or perhaps junk) DNA.

All of the above.

Eukaryotes have large amounts of extra (or perhaps junk) DNA.

As chromosome condensation occurs, a 300-angstrom fiber is formed. It appears to be composed of five or six ???

coiled together. Such a structure is called a ???

These fibers form a ???

that further condense into the chromatin fiber and are then coiled into chromosome arms making up each ???

nucleosomes

solenoid

series of loops

chromatid

Why does histone acetylation might be associated with

cancer?

Overacetylation is often associated with increased gene activity, which could lead to a cancerous state if proto-oncogenes were activated.

Normally, acetylation activates proto-oncogenes, which are responsible for the prevention of a cancerous state.

Histone acetylation promotes normal cell proliferation and mitosis leading to high expression of genes coding for proto-oncogenes.

Low acetylation rates often lead to increased cell proliferation, the major cause of tumor.

Overacetylation is often associated with increased gene activity, which could lead to a cancerous state if proto-oncogenes were activated.

What is the rationale for the use of HDAC inhibitors in the treatment of certain forms of cancer?

Select all that apply.

HDAC inhibitors may decrease expression of anti-division genes.

HDAC inhibitors may increase expression of anti-division genes.

HDAC inhibitors may decrease expression of pro-division genes.

HDAC inhibitors may increase expression of pro-division genes.

HDAC inhibitors may increase expression of anti-division genes.

HDAC inhibitors may decrease expression of pro-division genes.

If there were 75 naturally occurring amino acids then what is the smallest codon

size?

1

2

3

4

5

4

When scientists were attempting to determine the structure of the genetic code, Crick and coworkers found that when three base additions or three base deletions occurred in a single gene, the wild-type phenotype was sometimes restored. These data supported the hypothesis that________.

the code contains internal punctuation

the code is triplet

there are three amino acids per base

AUG is the initiating triplet

the code is overlapping

the code is triplet

A particular mRNA is 300 nucleotides long. If a mutation in the middle of the sequence changed a codon from a AAA to a UAA then what would be a reasonable

prediction?

The protein coded by this mRNA would kill the cell.

The protein coded by this mRNA would not form due to a failure in initiation.

The protein coded by this mRNA would be longer.

The protein coded by this mRNA would be shorter.

The protein coded by this mRNA would be the same size.

The protein coded by this mRNA would be shorter.

Choose a sequence of mRNA that codes for five amino acids. The mRNA should contain proper punctuation and

polarity.

3′-GUA CCA AAG CAC UAA-5′

3′-AUG GUA CCA AAG CAC UGA-5′

5′-GUA CCA AAG CAC UAA-3′

3′-UAU GUA CCA AAG CAC-5′

5′-AUG GUA CCA AAG CAC-3′

3′-AUG GUA CCA AAG CAC UGA-5′

5′-AUG GUA CCA AAG CAC UGA-3′

5′-UAU GUA CCA AAG CAC UAA-3′

5′-AUG GUA CCA AAG CAC UGA-3′

An mRNA that is being produced comes off of the

________.

template strand in both bacteria and eukaryotes

coding strand in both bacteria and eukaryotes

template strand in bacteria and the coding strand in eukaryotes

coding or template strand in both bacteria and eukaryotes depending upon the species

coding strand in bacteria and the template strand in eukaryotes

template strand in both bacteria and eukaryotes

A mutation in a particular bacterial gene prevents the formation of a hairpin loop. This is most likely to affect which part of

transcription?

This mutation will affect termination.

This mutation will affect initiation.

This mutation will not affect any aspect of transcription in bacteria.

This mutation will affect elongation.

This mutation will affect initiation, elongation, and termination.

This mutation will affect termination.

In a particular bacterial mutant, a specific gene is not producing a mRNA or the corresponding protein. Researchers sequence the gene and determine that there are no mutations in the coding portion of the gene. Choose the structures that could be mutated to explain these observations.

Select all that

apply.

termination sequences

Pribnow box (TATAAT)

splice sites

-35 sequence (TTGACA)

poly-A tail

Pribnow box (TATAAT)

-35 sequence (TTGACA)

A bacterial protein called rho factor binds to an mRNA at the ???

It moves along the ??? in a ???

direction chasing after the ???

When it reaches the ???

it removes it and then proceeds to break through the hydrogen bonds holding the ???

together, which successfully removes the RNA polymerase.

rut site

mRNA 5'-3'

RNA poly

hairpin loop

RNA-DNA

Most eukaryotic mRNAs are shorter than the genes that encode them. The reason for this is

_______.

exons are spliced out of the hnRNA

addition of the poly-A tail to the genomic DNA

eukaryotic genes contain both introns and exons

introns are spliced out of the DNA

eukaryotic genes contain both introns and exons