Genetics Exam 3 - Quiz Flashcards
According to Chargaff’s rule, if the DNA of a species contains 20% adenine, what percent of guanine will it contain?
30%
The first group of researchers to correctly identify the double-helix structure of DNA were
Watson and Crick
Avery, Macleod, and McCarty used the enzyme ____ to remove the proteins from the cell extracts
protease
The _____ was/were labeled using the radioisotope 32P in the Hershey-Chase experiments
DNA
Select the nitrogenous base found only in RNA
uracil
The building blocks of DNA are called
nucleotides
Which RNA structural pattern does NOT contain single-stranded regions
multi-branched junction
The backbone of the DNA molecule is formed by ___
phosphodiester bonds
In a double-helix DNA strand the adenine on one strand forms a hydrogen bond with a(n) ____ on the other strand
thymine
Select the feature that is incorrect about this double stranded DNA”
5’ - ATGCCCGGAAC - 3’
5’ - TACGGGCCTTG - 5’
The strand is not antiparallel
What is true in both phage lambda and HIV infections
There can be a long latent period where no sign of infection, such as cell death is detectable
A bacteriophage that is physically integrated into the host chromosome is called a ___
prophage
A ____ frequently integrates into the host genome, forming prophages and utilizing a lysogenic cycle to manufacture new phages
temperate phage
Vaccines have been very useful in preventing viral diseaSe. In fact, they have lead to the eradication of smallpox from the world’s human population. Most vaccines result in the host producing antibodies (proteins that bind to specific amino acid sequences) that bind to specific viral proteins. What might be a reason why a vaccine for HIV has been so difficult to develop
the high mutation rate of HIV
Which virus uses reverse transcriptase in its reporductive cycle
HIV
You perform an experiment like that performed by Fraenkel-Contrat and Singer on TMV. However, in the first step when the viruses are reconstituted, you decide to add RNase to your HR RNA and wild-type proteins. what will be the content of the newluy made viral proteins after he reconstituted viruses is placed on leaves
No new viral proteins will be made
What is the genetic material in the parvovirus
single-stranded DNA
What is the genetic material in the T4 bacteriophage
Double-stranded DNA
What is a property of emerging viruses
may lead to a significant loss of human life
recent origin
more likely to cause infection compared to other strains
If protein was the genetic material of TMV rather than RNA, what would be the result of the Fraekel-Contrat/Singer experiments when using HR proteins and wild-type RNA
HR type lesions, histidine and methionine in the capsid protein
How many origins of replication are there in a bacterial chromosome
1
where do kinetochores attach to chromosomes
centromeres
The majority of the non-repetitive genes in an organism are found in which of the following
unique sequences
The DNA of a bacterial cell must be compacted about ____ fold to fit within the confines of the cell
1000
The correct order of compaction from least to greateest
naked DNA
nucleosome
30nm fiber
loop
metaphase chromosome
You are performing an experiment to identify chromosome territories in a species with 6 pairs of homologous chromosome, plus two sex chromosomes. You use 7 different colored fluorescent molecules (one for each chromosome and one for the sex chromosome) and link each one to a probe that is highly conserved at the centromere of each chromosome in this species. what will be the result of your experiment
The chromosomes will all be marked but you won’t be able to tell which chromosomes in which
A double stranded stretch of eukaryotic DNA is 250,000 bp long. IF the average linker is about 54 bp how many nucleosomes would be present on this piece of DNA
1250
The formation of what structure would be impaired if a cell was lacking CTCF proteins
loop domains
Transposons that use an RNA intermediate for transposition are called
retrotransposons
A transposon is inserted into the sequence 5’ GACTC 3’ following simple transposition into the site, what sequences flank the transposon
5’ GACTC 3’
5’ GACTC 3’
In the attachment of a nucleotide to a DNA strand, the cleavage of the dNTP into deoxyribunucleoside monophosphate and pyrophosphate is ___
exergonic
How many DNA polymerase are found in prokaryotes
5
What enzyme relaxes supercoiling ahead of the replication fork
topoisomerase
What is the purpose of Okazaki fragments
To allow DNA to be synthesized in the 5’ to 3’ direction on the lagging strand
How many origins of replication does a bacterial chromosome contain?
1
In yeast, which of the following is similar to the oriC region of prokaryotes
ARS elements
If eukaryotic cells evolved such that lagging strand DNA synthesis could occur continuously (without the use of Okazaki fragments), what enzyme would likely no longer be needed for DNA replication?
flap endonuclease
What process does the Holliday model help explain
recombination between homologous chromosomes
You have isolated what appears to be alien DNA. While studying its replication, you performed the exact experiment Meselson and Stahl did. After three generations, the DNA is subjected to a CsCl gradient and only one band appears. What type of replication does this DNA undergo?
dispersive
Which describes the mechanism of DNA replication in which the newly made double-stranded DNA contains one parental strand and one daughter starnd?
semiconservative
What is the name of the site in eukaryotic DNA where general transcription factors associate?
promoter
Following transcription, the RNA has complementary sequence to
teh template strand of dna
In eukaryotic organisms, what process is important for the initiation of translation
5’ capping
What enables the splicing of group I and II introns
ribozymes
In eukaryotic organisms, what RNA modification is important for mRNA stability
3’ polyA tailing
Which subunit of the prokaryotic RNA polymerase carries out catalytic synthesis of RNA?
beta
Both the rho-dependent and rho-independent mechanisms of termination
involve the formation of a stem-loop structure
In eukaryotic organisms, what protein allows RNA polymerase II to interact with transcription factors bound to enhancers or silencers
mediator
A mutation occurs in one of the general transcription factors necessary for eukaryotic transcription. A pre-initation complex forms, but the open complex does not form. Further, TFIIB, TFIIE, and TFIIIH are not releaSed from the DNA. The mutation is most likely in which general transcription factor
TFIIH
What region in eukaryotic genes cotnains the majority of regualtory elements
-50 to -100
