Post on 10-Apr-2018
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Question Answer Hint
________ is the study of heredity. Genetics
Definition of Viruses Obligate intracellular Parasite
Proteobacteria
most gram-negative chemoheterotrophic bacteria.
largest taxonomic group of bacteria. phylogeny
based upon rRNA similarities. subgroups designated
by Greek letters.
This organism contains a single,
covalently closed circular molecule of
DNA?
Prokaryotes
What are viruses? obligatory intracellular parasites
Alpha Proteobacteria
includes most proteobacteria capable of growth
with low nutrient levels. some have
prosthecae(bud-like protusions). some
agriculturally important(nitrogen fixation). some
plant and human pathogens.
Characteristics of Viruses
Unable to exist independently from host cells. Can
direct life processes of host cells. Contain a sngle
type of nucleic acid (DNA or RNA) and a protion
coat, sometimes enclosed by an envelope
composed of lipids, proteins, and carbohydrates
The genetic information in a cell is called
the ___________.genome
This organism has several pieces of DNA
(complexed w/histones)in the cells
nucleus
Eukaryotes
What are the different components of
viruses?
contain DNA OR RNA, protein coat, some have an
envelope surrounding the coat, some have spikes,
MUST infect only specif types of cells in one host,
the host range is determined by specific host
attachments and cellular factors
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A cell's genome is organized into
______________.chromosomes
Do viruses contain DNA, RNA, or both? DNA or RNA (one or the other)
Rickettsia
gram-negative rod-shaped bacteria or coccobacilli.
obligate intracellular parasites. transmitted to
humans by bites of insects and ticks. infections
damage permeability of blood capillaries resulting
in a spotted rash.
This organisms genes are frequently split
into noncoding regions and coding
regions
Eukaryotes
What does obligate mean? Absolutely must
A cell's genetic information is organized
into ________________.chromosomes
Coding Regions are called? Exons
Rickettsia prowazekiiorganism that causes the disease epidemic
typhus(human body lice).
Size of Viruses
Smallest infectious agents must have electron
microscopes to see. From 20nm to 450 nm in
diameter
What is the host range of viruses? The range of the cells a particular virus will attack
A cell's ________ is organized into
chromosomes.genome
Components of a virus particleA Cellular contains only the parts needed to invade
and control a host cell.
Non Coding Regions are called? Introns
Rickettsia rickettsiiorganism that causes the disease Rocky Mountain
Spotted Fever. transmitted by ticks.
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What is the host range of a virus
dependent on?
specific host attachment sites and other cellular
factors
2 main components of a virus particle Central Core and External Covering
________ are structures containing DNA
that physically carry hereditary
information.
Chromosomes
A group of related genes that are
attached to one another are called?Operons
Do all viruses have a protein coat? Yes
Ehrlichia
gram-negative rickettsialike bacteria. obligate
intracellular parasites. live within white blood cells.
transmitted by ticks to humans. causes ehrilichiosis,
a sometimes fatal disease.
_________ carry genes. Chromosomes
Bartonellagram-negative baccilus. human pathogen.
Bartonella henselae causes cat-scratch disease.
Central core contains? Nucleic acid and preformed enzymes.
Do all viruses have an envelope
surrounding the protein coat?no, some do some don't
What does DNA mean? Deoxyribonucleic acid
Brucella
small nonmotile gram-negative coccobacilli.
obligate parasites of mammals. can survive
phagocytosis, an important element of body's
defense against bacteria. Brucellosis is disease that
is caused.
Characteristics of the Nucleic acid in a
virus?
has DNA or RNA not both. genome (genes of
organism) size is very small.
Chromosomes carry ________. genes
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Do all viruses have spikes? no, some do some don't
What does RNA mean? Ribonuicleic acid
Beta Proteobacteria
some overlap with alpha-proteobacteria. can use
hydrogen gas, ammonia, and methane for nutrient
production. some are pathogenic.
Fill in the blanks with these two words in
the proper order: chromosomes, genes.
________ carry _________.
chromosomes carry genes
What are the minmum genes contained
in the Nucleic acid in a virus?
Capsid synthesis, nucleic acid synthesis, regulation
of host processes (home invasion gene) and virus
packaging
What are viral species?a group of viruses sharing the same genetic
information and ecological niche
_______ are segments of DNA Genes
Bordetella
nonmotile, aerobic, gram-negative rod. serious
pathogen. Bordetella pertussis is the cause of
pertussis, or whooping cough.
Do all Viruses contain preformed
enzymes?No
What are plaques?bacteriophages form plaques on a lawn of bacteria
(congregates of cell death)
What kinds of bonds from between the
two strands of DNA?Hydrogen bonds
_______ are segments of DNA that code
for functional proteins.Genes
How are viruses identified?cytopathic effects, serological effects, and by the
nucleic acid tests
How many base pairs are formed in2
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DNA?
Neisseria
aerobic, gram-negative cocci. usually inhibits the
mucous membranes of mammals. pathogenis
species include Neisseria gonorrhoeae, the
causative agent of gonorrhea and Neisseria
meningitidis, the causative agent of meningoccal
meningitis.
What are some examples of preformed
enzymes that may exsist in viruses?polymerases, replicases and reverse transcriptase
_________ are repeating units that
compose the macromolecule of DNA.nucleotides
Gamma Proteobacterialargest subgroup and most diverse of
proteobacteria.
How many bonds stablize the base pair
Adenine-Thynine?2
What are serological effects?
A way to identify viruses. To see if the body is
making an antibody for the specific virus. Includes
neutralization tests, viral hemagglutinzation and
the western Blot.
What is the external covering of a virus
called?Capsid
Francisella
small gram-negative rod. human pathogen.
transmitted by wild animals and anthropods.
Francisella tularensis causes the disease tularemia.
How many bonds stablize the base pair
Cytosine-guanine?3
What are lytic viruses?lysis= cell deaht. Viruses that kill the host cell by
causing lysis.
What are nucleotides? repeating units that compose DNA
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What is the Capsid?
Protein "shell" that surrounds and protects nucleic
acid. Helps introduce nucleic acid into host.
Stimulates immune system.
Pseudomonas
aerobic, gram-negative rod. motile by polar flagella.
common in soil and other natural environments.
resistant to many antibiotics. opportunistic
pathogen. causes food spoilage. Pseudomonas
aeruginosa produces blue-green pigment.
What are the different stages of lytic
cycles?
attachment, penetration, biosynthesis, maturation
and release
What is a "nucleocapsid"? Capsid and Nucleic acid equals "nucleocapsid"
What is the structure of a nucleotide?
Each nucleotide consists of : - a nitrogenous base
(adenine, thymine, cytosine or guanine) -
deoxyribose ( a pentose sugar) - phosphate group
When we say the two strands are exact
oposite we are saying they are?Complementary
Describe the attachment stage of a lytic
cycle.The phage attaches by tail fibers to the host cell.
Moraxellastrictly aerobic coccobacilli. human pathogen.
Moraxella lacunata is implicated in conjunctivitis.
Strands that run in opposite direction
are said to be?Antiparallel
The ________ is an organism's genetic
makeup, the information that codes for
all the particular characteristics of the
organism.
genotype
What are subunits of Capsids called?Capsomers they self assemble to form helical or
icosahedral structures
Describe the penetration stage of the
lytic cycle.
The phage lysozyme opens the cell wall; tail sheath
contracts to force tail core and DNA into the cell.
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Legionella
aerobic, gram-negative rod. human pathogen.
common in streams and can grow in water-supply
lines. Legionella pneumophila causes the disease
legionellosis, a bacterial pneumonia.
The _________ refers to the actual,
expressed properties of an organismphenotype
What are the purines? Adenine and Guanine
What is the virus envelope?
External layer in some viruses. Derived from host
cell membrane when viruses are released.
Glycoprotein "spikes" on outside of envelope play a
role in attachment of viruses to host cells.
Coxiella
obligate intracellular parasites. cattle ticks harbor
the organism making it commonly transmitted by
aerosols or contaminated milk. Coxiella burnetti
causes Q fever(a bacterial pneumonia)
Describe the biosynthesis stage of the
lytic cycle.Production of phage DNA and proteins
Fill in the blanks with these two words in
the correct order: genotype, phenotype.
_________ is the manifestation of
__________.
phenotype is the manifestation of genotype.
Two requirements for viral
multiplication
requires a host cell and viruses must be able to
appropriate the synthetic and genetic machinery of
host
What are the Pyrimidines? Thynine and cytosine
An organism's ________ is its collection
of genes. genotype
Describe the maturation stage of the
lytic cycle.Assembly of phage particles.
Steps in Viral MultiplicationAdsorption, Penetration, Replication, Assembly and
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Maturation and Release
Vibrio
facultative anaerobic, gram-negative rods that are
often curved. human pathogen. transmitted mostly
by raw or undercooked shellfish. Vibrio cholerae
causes cholera, characterized by profuse, watery
diarrhea. Vibrio parahaemolyticus causes less
severe gastroenteritis.
When each new strand of DNA consists
of one old and one new strand we say
this is?
Semiconservative replication
An organism's ________ is its entire
DNAgenotype
Describe the release stage of the lytic
cycle.Phage lysozyme breaks the cell wall.
Escherichia facultative anaerobic, gram-negative rod.
What is a Bacteriophage? Viruses that infect Bacteria
An organism's _______ is its collection
of proteins.phenotype
Origin of replication for DNA occurs
most often at which bond? Why?
the A-T bond as it is only connected by 2 Hydrogen
bonds so it is weaker than C-G
What are lysogenic phages?phage DNA is incorporated into the host DNA. any
time the cell divides, the phage divides to.
What are the 2 multiplication cycles in
Bacteriophages?Lytic Cycle and Lysogeny
How do lytic and lysogenic phagesdiffer?
lysogenic can become lytic. lytic cannot becomelysogenic. lysogenic eventually becomes lytic.
The DNA within a cell exists as long
strands of _______ tiwsted together in
pairs to form a double-helix.
nucleotides
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This is the alternating sugar and
phosphate molecules held together by
convalent bonds
DNA backbone
What is the Lytic cycle?
Replication of viral nucleic acids and proteins
causes cell to be packed with virus. Causes lysis and
death of host cell
The DNA within a cell exists as long
strands of nucleotides twisted together
in pairs to form a ________.
double-helix
The phosphate spans from 3' carbon of
one sugar to 5' carbon of next, you
count clockwise from Oxygen
DNA Backbone
What are the sequence of events in the
lytic cycle?
Bacteriophage tail fibers bind to receptors on
bacteria. Viral nucleic acid is injected through
bacterial wall and membrane. Viral nucleic acid
redirects genetic and metabolic activities of cell.
Viral subunits spontaneously assemble. Host cell
lyses liberating virions.
What is generalized transduction?
transferring DNA from bacteria/host to the virus
cell. It is a RANDOM piece of DNA....accidentally
some virus DNA gets incorporated into the host.
Each strand of DNA is made up of what?
string of alternating sugar and phosphate groups,
with a nitrogenous base attached to each sugar in
the backbone.
What is specific transduction?
taking a specific portion of DNA from the host cell.
It is a special part of the DNA that is transferred
from the host to the virus cell.
What is the main difference in Lytic cycle
and Lysogeny?
"temperate" bacteriophages undergo adsorption
and penetration but are not replicated or released.
Host cell is not lysed
When it is comprised of 2
complementary and antiparallel strands
Double Helix
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we say it is a ?
Lysogeny is equal to? Latency
What are the steps in an animal viral
cycle?
attachment, penetration, uncoating, biosynthesis,
maturation, release by budding OR rupture
What is the sugar phosphate backbone?
a string of alternating sugar and phosphate groups,
with a nitrogenous base attached to each sugar of
the backbone.
When each strand of the orginal
molecule serves a template for the
synthesis of a complementary copy
DNA Replication
Adenine always pairs with _________. thymine
Examples ofLysogenic phages are? Herpes Viruses, cold sores shingles
How are lytic cycles different from
animal viral cycles?
animal viral cycles have an "uncoating" step and the
penetration step is different; in animals the entire
virus goes in not just the genetic information.
How do animal viruses enter the cells? via pinocytosis or fusion
Other characteristics of lysogeny are.
Viral DNA is inserted into bacterial chromosome.Prophage is retained by bacterial cell and is copied
during cell division. progeny also carry temperate
phage. Viral genome is not expressed. Prophage in
lysogenic cell can be excised from host
chromosome and initiate lytic cycle.
Thymine always pairs with ________. adenine
A complete, fully developed viral particle
composed of nucleic acid surrounded bya coat is known as?
Virion
Guanine always pairs with _________. cytosine
How do enveloped animal viruses bud? steals membrane from the host
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Bacteria have how many Origins of
Replications?one
Cytosine always pairs with ________. guanine
Explain the attachment step of the
animal viral cycleviruses attach to the cell membrane
Eukaryotic cells have how many ORI?
why?Multiple ORI to speed up replication
explain the penetration step of an
animal's viral cycleentire virus goes in via endocytosis or fusion
What are the purines? adenine and guanine
explain the uncoating step of an animal's
viral cycleThe DNA or RNA of host is cut
What are the pyrimidines? cytosine and thymine
What is the initial primer for DNA
Polymerase III to start catalyzing?RNA
explain the biosynthesis step of an
animal's viral cycleproduction of nucleic acid and proteins
The base pairings of nucleotides are
________.complementary
The two strands at the replication fork
are called the?leading strand and lagging strand
explain the maturation step of an
animal's viral cyclenucleic acid and capsid proteins assemble
The two strands of DNA are _________. complementary
explain the release step of an animal's
viral cycle
release is by budding if enveloped, if not then
ruptures
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This strand runs 5' phosphate to 3'
hydroxyl and DNA synthesis occurs
continously
Leading strand
This strand runs 3' to 5' and synthesis
occurs discontinously Lagging strand
What are transformed cells?
activated oncogenes transform normal cells into
cancerous cells. These transformed cells have
increased growth, loss of contact inhibition.
What are oncogenic viruses?The genetic material of oncogenic viruses becomes
integrated into host cells.
What are the fragments called that
Lagging strand synthesis uses they are 5'
to 3'
Okazaki fragments
What is the difference between
oncogenic viruses and transformed
cells?
Oncogenic viruses may cause the occurence of
transformed cells. Oncogenic viruses are thus
named because the genetic material of cancer
causing viruses becomes integrated into host cells.
These host cells are transformed cells.
What are latent viral infectoins?
When a virus remains asymptomatic in the host cell
for long periods of time.
What are persistent viral infectoins?disease processes occur over a long period of time;
generally it is fatal.
What are the difference between latent
and persistent viral infections?
in latent viral infections, the host cell remains
asymtomatic for long periods of time. In persistent
viral infections, the symptoms show up slowly over
the course of a long period of time.
What are prions?
They change the normal protein! Prions are
proteins that can infect! They are inherited and
transmissile by ingenstion, transplant and surgical
instruments.
True or false: Viruses are the smallestFalse: prions are smaller than viruses!
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material that can kill you.
How are prions transmitted?inherited, ingested, on non-sterile
transplant/surgical instruments
Transcription is what? DNA to RNA
What is PrPc?An example of a normal cellular prion protein
located on a cell's surface.
What is PrPsc?A scrapie protein; accumulates in brain cells, forms
plaques.
How do plant viruses enter? through wounds or via insects
What are viroids?normally found in plants, not animals. Small pieces
of RNA that are infectious.
What term best describes the
statement: "Small pieces of RNA that are
infectious."
viroids
Genes coding for related enzymes
frequently occur together in a clusterOperon
in mRNA 3 bases together is a codon
One codon specifies 1 amino acid
The start codon is AUG Methionine
The 3 stop codons or nonsense codons
are?UAA, UAG, UGA
UAA, UAG, UGA can be remembered by U Are Awful, U Are Gross, U Go Away
Most amino acids are signaled by several
alternative codons a situation referred
to as the
Degeneracy of the code
3 bases in DNA are defined as a Triplett
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3 bases in mRNA are defined as a Codons
3 bases in tRNA are defined as a Anti codons
RNA synthesis = Transcription
When biosynthetic enzymes are not
produced if their product is present in
the medium
Enzyme Repression
In Enzyme repression _____ is usually
the final product of an anabolic pathwayeffector("co-Repressor")
Enzyme is synthesized only when its
substrate is presentEnzyme Induction
Organism does not waste energy
synthesizing unneeded enzymesEnzyme Repression
Organism does not synthesize enzymes
until they are neededEnzyme Induction
Induction and repression act at the level
ofTranscription
These enzymes are not subject toinduction or repression and synthesize
continuously in the growing cell
Constitutive enzymes
These are key cellular enzymes required
for growth under all nutritional
conditions
constitutive enzymes
This is a heritable change in the
nucleotide sequence of DNAMutation
Two classes of mutations Frame shift and point mutations
3 types of point mutations Silent, Missense, Nonsense
DNA is synthesized in the _______5'-------->3'
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direction.
RNA synthesis continues until RNA
polymerase reaches a site on the DNA
called the _________.
terminator
What is the terminator?a site on the DNA that "signals" RNA polymerase to
stop synthesizing RNA
______ are the regions of DNA that are
expressedexons
_______ are the regions of DNA that do
not encode protein.introns
What are constitutive genes?
their products are not regulated; their products are
constantly produced at a fixed rate. Usually these
genes are effectively turned on all the time, so they
code for enzymes that the cell needs in fairly large
amounts.
What is repression?the regulatory mechanism that inhibits gene
expression and decreases the synthesis of enzymes
What term is best described by the
following: " The regulatory mechanism
that inhibits gene expression and
decreases the synthesis of enzymes is
called _______. "
repression
Repression is mediated by regulatory
proteins called ________.repressors
What do repressors do?they block the ability of RNA polymerase to initiate
transcription from the repressed genes
What is the process that turns on the
transcription of a gene/genes?induction
What is induction?the process that turns on the transcription of a
gene/genes
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A substance that acts to induce
transcription of a gene is called an
________
inducer
what is an inducer?
a substance that acts to induce transcription of a
gene
Enzymes synthesized in the presence of
induces are ___________.inducible enzymes
the combination of an operator,
promeoter, and the structural genes
they control is known as _______
an operon
What is an operon?
the combination of an operator, promotor, and the
structural genes they control.
How are inducible operons and
repressible operons different?
In inducible operons, the structural genes are
transcribed when they are turned on, or induced. In
repressible operons, the structural genes are
transcribed UNTIL they are turned off, or repressed.
An example of an inducible operon is the
_______ operon.lac
An example of a repressible operon is
the _________ operon.tryptophan
Inhibition of the metabolism of
alternative carbon sources by glucose is
termed ___________.
catobolite repression
catobolite repression is also known as
the ___________.glucose effect
__________ is also known as the glucose
effect.catobolite repression
How does catabolite repression work?keeps making C-amp until turned off by realizing
that the body has enough glucose.
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What is a bse mutation?a single base at one point in the DNA sequence is
replaced with a different base.
What is a missense mutation?
If a base situation results in an amino acid
substitution in the synthesized protein, it is referred
to as a missense mutation
What term is best described: " a base
situation results in an amino acid
substitution in the synthesized protein "
missense mutation
What term is best described: " a base
substitution resulting in a stop
(nonsense) codon "
nonsense mutation
What is a nonsense mutation?
When a base substitution results in a stop
(nonsense) codon, preventing the synthesis of a
completely functional protein.
What is a frameshift mutation?When one or a few of the nucleotide pairs are
deleted or inserted in the DNA
What term is best described: " When
one or a few of the nucleotide pairs are
deleted or inserted in the DNA"
frameshift mutation
Spontaneous mutations are what?when mistakes occur during DNA replication in the
absence of an apparent mutation-causing agents.
What term is best described: " when
mistakes occur during DNA replication in
the absence of an apparent mutation-
causing agent "
spontaneous mutation
What are mutagens?
agents in the environment, such as certain
chemicals and radiation, that directly or indirectly
bring about mutation
What term is best described: " agents in
the environment, such as certain
chemicals and radiation, that directly or
mutagens
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indirectly bring about mutation "
How do chemical mutagens work?
convert the base adenine (A) to form in such a way
that it no longer pairs with thymine (T), but with
cytosine (C).
How do ionizing radiation cause
mutations?
causes the formation of ions and free radicals that
react with DNA and can break the sugar-phosphate
backbone or cause base substitutions
UV radiation causes mutations how? by causing bonding between adjacent thymines
How are thymine dimers repaired?thymine dimers can be repaired by light-repair
enzymes
What do light-repair enzymes do? repair thymine dimers
________ involves detection of mutant
cells by rejection of the unmutated
parent cells
positive (direct) selection
In lameman's terms, what does this
mean: " involves detection of mutant
cells by rejection of the unmutated
parent cells "
you want the mutants!
What term is best described: " this
process selects a cell that connot
perform a certain function "
negative (indirect) selection
Positive selection is ________. direct
Negative selection is _______. indirect
Another term for direct selection is
__________.positive selection
another term for indirect selection is
____________.negative selection
What is replica plating technique usednegative selection
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for?
_________ is a relatively inexpensive
and rapid test for identifying possible
chemical carcinogens.
Ames test
What does the Ames test identify? posisble chemical carcinogens
What does the Ames test assume?
that a mutant cell can revert to a normal cell in the
presence of a mutagen, and that many mutagens
are carcinogenic
In prokaryotes, transcription occurs in
the _________cytoplasm
In eukaryotes, transcription occurs in the
________nucleus
" ATGCTATTG " is an example of a code
for DNA or RNA? How can you tell?DNA: presence of thymines
" AUGCUAUUG " is an example of a code
for DNA or RNA? How can you tell?RNA: presence of uracil
In DNA, adenine pairs with __________. thymine
In RNA, adenine pairs with __________. uracil
an MRNA is read in what direction? 5'------->3'
There are _____ codons. 64
In prokaryotes, __________ can begin
before transcription is complete.translation
In _________, translation can beginbefore transcription is complete
prokaryotes
Genes for the enzymes in glycolosis are
examples of what type of enzymes?constitutive enzymes
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The start codon codes for the amino acid
_________.methionine
Another word for the stop codon is a
________ codon.nonsense
What is a gene?a segment of DNA that describes the instructions
for creating a polypeptide chain
What is best described by the following
statement: " a segment of DNA that
describes the instructions for creating a
polypeptide chain"
gene
A gene is _________ to form mRNA. transcribed
An mRNA molecule is _________ to
form a protein.translated
Protein synthesis can be divided into
three steps. What are they?
1. transcription 2. pre-mRNA processing 3.
translation
Where does transcription occur? in the nucleus
Where does pre mRNA processing
occur?in the nucleus
Where is mRNA formed? in the nucleus
Where does translation occur? in the cytosol / free floating ribosome
Where is protein officially synthesized? in the ribosome in cytosol
What is the definition of transcription? the synthesis of mRNA from a DNA template
Transcription is the synthesis of _______from ________.
mRNA ; DNA template
Transcription occurs in three stages.
What are they?1. Initiation 2. Elongation 3. Termination
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Transcription factors bind to the
_________, a sequence specifying the
start of the gene.
promoter region of DNA
What are transcription factors?
they bind to the promoter and signal the RNA
polymerase to bind to DNA to initiate transcription.
Transcription factors bind to the
promoter region of DNA, a sequence
specifying the _________ of the gene.
start site
Transcription factors signal the binding
of _________ near the start site.RNA polymerase
___________ binds to the promoter,
pries the two DNA strands, and initiates
mRNA synthesis at the start point on the
template strand.
RNA polymerase
RNA polymerase initiates mRNA
synthesis at the start point on the
_______ strand.
template
The mRNA formed will have the same
sequence as the ________ strand of
DNA. (except thymines will be replaced
with uracils)
coding
The mRNA formed will have a sequence
complementary to that of the _______
strand of DNA.
template
RNA polymerase enzyme does what?
oversees the synthesis of mRNA by unwinding the
DNA template and moving along the DNA to add
nucleotides to the mRNA that complement the DNA
template strand
RNA polymerase _______ the DNA
template.unwinds
RNA polymerase moves along DNA and
adds _________ to the mRNA that
nucleotides
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complement the DNA template strand.
As the RNA polymerase moves along the
template strand, elongating the mRNA
transcript one base at a time it ______
the DNA double helix before it and
rewinds the double helix behind it.
unwinds
At any given moment, 16-18 pairs of
DNA are unwound and the most recently
made RNA is still bound to DNA. This
small region is called the _________.
DNA-RNA hybrid.
RNA polymerase reaches the gene's
___________ on the DNA, and releases
pre-mRNA.
termination signal
mRNA synthesis ends when?
When RNA polymerase reaches the termination
signal. RNA polymerase and the completed mRNA
transcript are released
What occurs during pre-mRNA
processing?1. RNA splicing 2. Cap and tail are added to mRNA
What does it mean to say that RNA is"spliced?"
- introns (intervening sequences) are removed by
spliceosomes - exons (expressed sequences are
brought together to form mRNA)
What are introns?
intervening sequences that are removed from the
final mRNA product during pre- mRNA processing
by spliceosomes
What are exons?expressed sequences that are joined together
during pre-mRNA processing.
Where are introns sliced out of the RNA
product?in the nucleus
mRNA is transported out of the ______
into the cytoplasm right before
translation.
nucleus
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mRNA is transported out of the nucleus
into the ________ for translation.cytosol
What is translation?the synthesis of a polypeptide from an mRNA
template.
What process is best described as: " the
synthesis of a polypeptide from an
mRNA template "
translation
What three types of RNA are involved in
translation?mRNA, tRNA and rRNA
What is best described by the following
statement: " carries instructions for
building a polypeptide, from gene in
DNA to ribosomes in cytoplasm "
mRNA
What is best described by teh following
statement: " a structural component of
ribosomes that, along with tRNA, helps
translate message from mRNA"
rRNA
What is best described by the following
statement: " Bind to amino acids and
pairs with bases of codons of mRNA at
ribosome to begin process of protein
synthesis"
tRNA
During translation, sets of three
nucleotides called ______ specify each
amino acid.
codons
What are codons?sets of three nucleotides that specify a particular
amino acid
What do mRNA's do in protein
synthesis?
carry instructions for building a polypeptide from
gene in DNA to ribosomes in cytoplasm
What do rRNA's do in protein synthesis? serve as structural components of ribosomes
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What do tRNA's do in protein synthesis?
bind to amino acids and pair with bases of codons
of mRNA at ribosome to begin process of protein
synthesis.
tRNA's bind to ________ and pair with
bases of codons of mRNA at ribosome to
begin process of protein synthesis.
amino acids
tRNA's bind to amino acids and pair with
bases of _______ of mRNA at _______
to begin process of protein synthesis.
codons ; ribosome
a tRNA molecule carrying the
complementary anticodon and the
corresponding amino acid binds to the
______ during translation
codon
a tRNA molecule carrying the
complementary _________ and the
corresponding amino acid bind to the
codon during translation.
anticodon
a tRNA molecule carrying the
complementary anticodon and the
corresponding ________ bind to the
codon during translation.
amino acid
mRNA attaches to the ______ during
translation.ribosome
a _______ molecule carrying the
complementary anticodon and the
corresponding amino acid bind to the
codon during translation.
tRNA
a tRNA molecule carrying the
complementary anticodon and the
corresponding amino acid bind to the
codon during _________.
translation
_______ attaches to the ribosomemRNA
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during translation.
The first codon enters the " _____ " site
of the ribosome.A
the first ______ enters the " A " site of
the ribosomecodon
The first codon enters the "A" site of the
________.ribosome
the ribosome moves along the ______
strand during translation.mRNA
Codons move from the "A" site to the
"_____" site to the "E" site while being
read by the ribosome during translation.
P
Codons move from the "A" site to the
"P" site to the _____ site while being
read by the ribosome during translation.
E
After leaving the "E" site, the tRNA is
released back into the cytoplasm where
a new _______ will be attached to it.
amino acid
When the ribosome reaches the stop
codon on the mRNA, what happens?the polypeptide is released
What has to happen for the polypeptide
to be released during translation?the ribosome has to reach the stop codon.