Frage 1
Frage
In RNA, glycosidic bonds occur between:
Antworten
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ribose and nucleotide base ribose and nucleotide base
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deoxyribose and nucleotide base
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ribose and phosphate
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deoxyribose and phosphate
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two nucleotide bases
Frage 2
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Chromatin structure
Antworten
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Is constant across each chromosome
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Strongly influences gene expression Strongly influences gene expression
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Cannot impact heritable traits
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Requires only a few proteins
Frage 3
Frage
Writer and Eraser enzymes (more than one answer may apply)
Frage 4
Frage
Gene duplication (more than one answer may apply)
Antworten
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Creates an opportunity for organisms to diversify
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Always results in new functions
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Damages the DNA irreparably
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Provides a mechanism for altering the function of the gene product
Frage 5
Frage
Transgenic organisms (more than one answer may apply)
Antworten
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Utilize somatic gene transfer
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Contain a "foreign" gene introduced into the germ line
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Have been created in only limited numbers
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Pass on their transgenes to progeny
Frage 6
Frage
DNA is replicated 5' to 3'. Why is this directionality the only one observed in living organisms?
Antworten
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Because of the anti-parallel nature of DNA
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Because RNA synthesis is required
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Because of the energy requirement for fidelity/proof-reading
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Because the ssDNA binding proteins bind 5' to 3'
Frage 7
Antworten
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Codes directly for proteins without any intermediary
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Is contained in the nucleus in prokaryotes
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Utilizes hydrogen bonds to maintain sugar-phosphate backbone stability
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None of the above
Frage 8
Frage
"Dideoxy" (or Sanger) sequencing of DNA
Antworten
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Uses deoxynucleotides for chain termination
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Can be performed using chemical methods
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Requires the ability to recognize the base at each position
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Relies on DNA polymerase that must be thermally stable
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Engages DNA ligase and ssDNA binding proteins
Frage 9
Frage
Transposons (more than one answer may apply):
Antworten
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Are mobile elements that can insert into any DNA sequence
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Come in a single type
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Are found in both prokaryotes and eukaryotes
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Can be easily "cured" (eliminated from an organism)
Frage 10
Frage
Okazaki fragments at the replication fork for DNA synthesis (more than one answer may apply):
Antworten
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Are essential for leading strand synthesis
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Are essential for lagging strand synthesis
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Are comprised only of deoxyribonucleotides
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Are comprised only of ribonucleotides
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Are comprised of ribonucleotides and deoxyribonucleotides
Frage 11
Frage
DNA repair (more than one answer may apply):
Antworten
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Does not target all DNA
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Preserves genetic information for the next generation of cells/organism.
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Involves only a small number of proteins
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Is confined to only two classes of DNA damage
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Requires 3-5% of coding regions in higher organisms
Frage 12
Frage
Indicate the functions associated with DNA polymerase [more than one answer may apply]:
Antworten
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Polymerizes nucleotides from 5' to 3'
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Creates RNA primers
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Exhibits 3' to 5' exonuclease activity
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Exhibits 5' to 3' exonuclease activity
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Seals together Okazaki fragments
Frage 13
Frage
The Avery-McLeod-McCarty experiment provided evidence that __________ and not ___________serves as the genetic material:
Antworten
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Proteins | DNA
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RNA | Proteins
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DNA | Proteins
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Polysaccharides | DNA
Frage 14
Frage
The role of telomerase is:
Antworten
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To extend the 5'-end of linear DNA
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To shorten the 5'-end of linear DNA
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To extend the 3'-end of linear DNA
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Not important to normal cells
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Dependent on an internal DNA template for extending DNA
Frage 15
Frage
Nucleosome structure (more than one answer may apply]:
Antworten
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Is driven primarily by RNA components
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Is invariant across a single chromosome
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Strongly influences gene expression and can determine epigenetic traits
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Is formed by DNA wrapping in a right-handed direction around the core histone octamer
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Is more loosely packaged when lysines in the histones are acetylated
Frage 16
Frage
Which of the following has a function in both the leading and lagging strand during replication (more than one answer may apply]?
Antworten
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DNA polymerase
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DNA ligase
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ssDNA binding proteins
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Okazaki fragments
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DNA clamp loader
Frage 17
Frage
Somatic gene therapy
Antworten
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Generates effects that can be inherited
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Affects germ cells primarily
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Can result in the production of a protein required by an individual
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Has no side effects
Frage 18
Frage
Place the following in order of assembly from the most basic structure to the most complex (type in letters without spaces or commas as in abcde):
a. Folded solenoid
b. Condensed chromatin
c. Solenoid structure
d. "Naked" DNA
e. Nucleosomes
Frage 19
Frage
In a DNA microarray experiment, you use two different short ssDNAs as probes, one with a label that fluoresces green (green DNA probe) and the other fluoresces red (red DNA probe). Note that an equal mixture of the two probes appears as yellow. The results shown below were obtained following completion of the experiment.
Which of the following can you conclude from the results (more than one answer may apply)?
Antworten
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The DNA samples in A2, A5, and C4 contain similar sequences to the green DNA probe but not to the red DNA probe.
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The DNA samples in A2, A5, and C4 contain complementary sequences to the green DNA probe but not to the red DNA probe.
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The DNA samples in B1, C5, and D2 contain similar sequences to the red DNA probe but not the green DNA probe.
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The DNA samples in B1, C5, and D2 contain complementary sequences to the red DNA probe but not the green DNA probe.
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The DNA samples in B3, B4, C2, and D1 contain similar sequences to both the green DNA probe and the red DNA probe.
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The DNA samples in B3, B4, C1, and C2 contain complementary sequences to both the green DNA probe and the red DNA probe.
Frage 20
Antworten
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Is carried out by multiple independent proteins that do not associate
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Utilizes the DNA clamp and clamp loader to coordinate the leading and lagging strands
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Differs significantly in prokaryotes and eukaryotes in the basic proteins required
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Results in high levels of errors that cannot be repaired by DNA polymerase activity
Frage 21
Frage
Polymerase Chain Reaction (PCR) is....
Antworten
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The key process in RFLP analysis
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Limited to genomic DNA
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Used to amplify DNA sequences
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Is the key process for DNA cloning
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Performed at a single temperature
Frage 22
Frage
The sugars (to which the bases in DNA are linked) are connected to one another by what type of bond?
Antworten
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Alpha-glycosidic
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Beta-glycosidic
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Phosphodiester
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Peptide
Frage 23
Frage
The nucleotide sequence of one DNA strand is 5'-GGATTTTTGTCCACAATCA-3'. The sequence of the newly synthesized daughter strand is:
Antworten
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5'-CCTAAAAACAGGTGTTAGT-3'
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5'-TGATTGTGGACAAAAATCC-3'
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5'-ACTAACACCTGTTTTTAGG-3'
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5'-GGATTTTTGTCCACAATCA-3'
Frage 24
Frage
The properties of histones (more than one answer may apply):
Frage 25
Frage
Which of the following are fundamental processes of DNA repair (more than one answer may apply)?
Frage 26
Frage
The key recognition surface for proteins to discern sequence in the 3-dimensional structure of a DNA is:
Frage 27
Frage
Origins of replication are rich A-T base pairs:
Antworten
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To be recognized readily
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To facilitate ease of opening to initiate transcription
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To promote primase binding
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To ensure a unique sequence
Frage 28
Frage
Which of the following is accurate regarding the DNA replication process (more than one answer may apply)?
Antworten
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No mistakes are made during this process
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Multiple proteins are involved
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Low mutation rate (i.e., few errors) is essential for survival of the organism
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Follows a conservative mechanism
Frage 29
Frage
Sequences of genes generated by duplication (more than one answer may apply):
Antworten
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Do not recombine to generate new functions for the encoded protein
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Can diverge significantly and maintain similar function
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Can diverge significantly and exhibit different functions
-
Never diverge in sequence
Frage 30
Frage
Eukaryotic DNA replication
Antworten
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Initiates at a single origin
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Requires duplication of histones as well as DNA strands
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Uses mechanisms that destroy patterns of histone modification
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Utilizes enzymes that differ significantly from prokaryotic replication
Frage 31
Antworten
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Contain two sets of three histone monomers
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Include histone and non-histone proteins
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Package DNA into a compact form
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Are more tightly packaged when serine is phosphorylated
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Are more tightly packaged when lysine is acetylated
Frage 32
Frage
Chromosomes within cells (more than one answer may apply):
Antworten
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Are randomly located
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Occupy distinct physical regions where genes are silenced and where genes are expressed
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Contain genes fixed in a precisely ordered pattern that corresponds to order of expression
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Move when expressed to a central region of the cell
Frage 33
Frage
The orientation of replication by DNA polymerases from 5' to 3' using 5'-dNTPs (more than one answer may apply):
Antworten
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Is required to ensure that the complementary strand is oriented anti-parallel
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Provides energy from the release of pyrophosphate (and its hydrolysis) to drive the reaction forward
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Allows proofreading by DNA polymerases
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Is not universal in all organisms
Frage 34
Frage
Restriction nucleases:
Antworten
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Are required to sequence DNA
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Are required to reproducibly generate specific fragments of DNA
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Protect DNA in eukaryotic organisms
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Cannot be helpful in identifying individuals
Frage 35
Frage
In DNA, hydrogen bonds occur between:
Antworten
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Ribose and nucleotide base
-
Deoxyribose and nucleotide base
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Two deoxynucleotide bases
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Ribose and phosphate
-
Deoxyribose and phosphate
Frage 36
Frage
Which of the following does NOT characterize the DNA replication process?
Antworten
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Mistakes can be made during the replication process, but most are detected and corrected by DNA polymerases
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This process utilizes a semi-conservative mechanism
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Organisms can generally tolerate a high error rate in replication
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This process engages a large number of proteins
Frage 37
Antworten
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Are composed solely of amino acids
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Are found in both prokaryotes and eukaryotes
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Protect the ends of linear DNA Protect the ends of linear DNA - correct
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Synthesize DNA 3' to 5'
Frage 38
Frage
Transposons (more than one answer may apply):
Antworten
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Move in a distinct pattern
-
Move in a more or less random pattern
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Can use different types of deletion/insertion strategies
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Are similar across all organisms
-
Can replace telomerase in some organisms
Frage 39
Antworten
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Has numerous highly repetitive sequences
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Contains approximately 3 million base pairs
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Contains approximately 3 million genes that encode proteins
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Uses over 30% of the sequence in coding proteins
Frage 40
Frage
DNA ligase (more than one answer may apply):
Antworten
-
Synthesizes DNA primers
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Has an important role in lagging strand synthesis during replication
-
Has an important role in leading strand synthesis during replication
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Seals recombinant DNA sequences with overlapping ends
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Unzips double-stranded DNA
Frage 41
Frage
The proteins for DNA replication that are NOT involved directly at the moving replication fork include (more than one answer may apply):
Antworten
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DNA polymerase
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DNA primase
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DNA helicase
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Topoisomerase
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ssDNA binding protein
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DNA ligase
Frage 42
Frage
Homologous recombination:
Antworten
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Is restricted to eukaryotes that are diploid
-
Is only used in repairing dsDNA breaks that occur randomly
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Is a complex process that repairs dsDNA breaks
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Does not require strict control
Frage 43
Frage
Which of the following sequences would denature from the sequence 5'-CGATGTCC-3' at the highest temperature?
Antworten
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5'-CGATGTCC-3'
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5'-GCTACAGG-3'
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5'-GGACATCG-3'
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5'-ATGCGCTA-3'
Frage 44
Frage
In prokaryotes, what protein binds first to DNA to start the replication process?
Antworten
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Helicase
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DnaA
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DNA primase
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Topoisomerase
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DNA polymerase
Frage 45
Frage
Epigenetic information (more than one answer may apply):
Antworten
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Is randomized when the DNA is copied
-
Is present in the DNA sequence
-
Depends on modifications of histones
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Is fixed and unchanging
-
May be influenced by environmental impacts
Frage 46
Frage
DNA size (in terms of number of base pairs) varies significantly among eukaryotic organisms. Which of the following is an accurate statement:
Antworten
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Gene size (in terms of number of base pairs) is directly proportional to DNA size
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Gene density (number of genes per base pair) differs between eukaryotic organisms
-
Gene density in eukaryotes is similar to prokaryotic organisms
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The number of genes is directly proportional to the number of chromosomes
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The number of genes is directly proportional to DNA size
Frage 47
Frage
Restriction nucleases (more than one answer may apply):
Antworten
-
Recognize specific sequences in DNAs and break both strands within this sequence
-
Are found in almost all molds
-
Were designed from other types of nucleases to fragment DNA
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Generate staggered ends or blunt ends
Frage 48
Frage
Regulation of DNA expression
Antworten
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Targets the same genes in the same way for all species
-
Is unimportant
-
May vary significantly for the same organ in different species May vary significantly for the same organ in different species - correct
-
Is the same for all cell types
Frage 49
Frage
The first synthetic step in DNA replication requires
Frage 50
Frage
What amino acids would you expect to find frequently modified in histones (more than one answer may apply)?
Antworten
-
Glutamic acid
-
Glycine
-
Lysine
-
Serine
-
Tryptophan
Frage 51
Frage
DNA replication (more than one answer may apply)
Antworten
-
Generates two identical copies of dsDNA with one strand that is "parental" and one strand that is "daughter"
-
Is continuous on both strands of the DNA
-
Is highly accurate in terms of maintaining the sequence
-
Requires protection of the exposed ssDNA segments
-
Requires synthesis of a DNA primer to start the process of copying each DNA strand
Frage 52
Frage
PCR requires (more than one answer may apply)
Antworten
-
All 4 deoxynucleoside triphosphates
-
A single dideoxynucleoside triphosphate
-
dsDNA
-
RNA
-
Oligonucleotide primers
-
Temperature-stable DNA polymerase
Frage 53
Frage
Regulation of DNA expression:
Antworten
-
Is not importantIs not important
-
Is the same for all species
-
Is essential in determining what proteins are produced Is essential in determining what proteins are produced - correct
-
Is determined by protein coding regions
Frage 54
Frage
Plasmids (more than one answer may apply):
Antworten
-
Can be used to amplify recombinant DNA
-
Are found primarily in eukaryotes
-
Are separate from chromosomal DNA and replicate independently
-
Are generally small, linear DNAs
Frage 55
Frage
The leading template strand is oriented from __________, and its complementary strand is oriented from ____________.
Antworten
-
3' to 5' | 3' to 5'
-
3' to 5' | 5' to 3'
-
5' to 3' | 5' to 3'
-
5' to 3' | 3' to 5'
Frage 56
Frage
Single nucleotide polymorphisms (SNPs) (more than one answer many apply):
Antworten
-
Are uncommon in genomes within the same species
-
Can be associated with changes in protein sequence that may predispose individuals to diseases
-
Are easily identified by DNA sequencing
-
Are single base pair changes
-
Are of little interest
Frage 57
Frage
Epigenetic changes (more than one answer may apply):
Antworten
-
Can appear at any age
-
Arise due to DNA sequence changes
-
Affect each cell in the same way
-
Can arise randomly
-
Can be generated from lifestyle impacts
Frage 58
Frage
Chargaff and colleagues demonstrated in the 1940's that the molar amounts of adenine and thymine in DNA were equivalent (%A = %T) and a similar equivalency applied to guanine and cytosine (%G = %C) (the "pair rule"). From this one can deduce that:
Antworten
-
Adenine and guanine will always be present in different molar amounts
-
Cytosine and thymine will always be present in different molar amounts
-
Purines and pyrimidines will always be present in different molar amounts
-
Purines and pyrimidines will always be present in equivalent molar amounts
Frage 59
Frage
Replication in eukaryotes (more than one answer may apply):
Antworten
-
Is fundamentally different from prokaryotes
-
Requires a complex composed of multiple proteins to begin the process
-
Starts at the same time at each of the replication origins
-
Starts at a single replication origin
-
Occurs during the S phase of the cell cycle
Frage 60
Frage
The multi-protein complex generated by the clamp loader formed at the replication fork
Antworten
-
Lowers the amount of energy required for replication
-
Increases the amount of energy utilized by DNA polymerase
-
Provides coordination of leading and lagging strands Provides coordination of leading and lagging strands - correct
-
Is designed to protect ssDNA