Genetics Exam 4 - Quiz Flashcards
which process is used to replicate DNA that contains distortions due to unrepaired DNA damage?
Translesion synthesis
Which DNA repair process utlizes MutL, MutH, and MutS proteins in E. Coli
Mismatch repair
Mutations that change the configuration of a protein at a specific temperature are called _____ mutations
conditional
What is an example of a suppressor mutation?
An intragenic mutation that restores protein structure
an intergenic mutation that increases the activity of a protein performing the same function as the mutated protein
an intergenic mutation that alters a transcription factor to active the expression of compensating protein
How does position effect influence gene expression?
The movement of the genetic material on the chromosome by inversions or translocations may place a coding sequence near a new regulatory region, thus activating the expression of the gene
The movement of the gene may place it into a region that is highly condensed
The movement of a gene may remove it from its normal promoter, thus silencing the gene
After screening a colony of bacteria for a given gene, you discover 100 mutant colonies out of 3 million total colonies. What is the mutation rate for this gene in the population?
3.3 * 10^-5
Which of the following integrate into the double helix of DNA, interfering with DNA replication
Arcidine dyes
The results of the replica plating experiments by the Lederbergs supported which of the following theories?
Random mutation theory
Most trinucleotide repeat expansion repeats involve expansion of which of the following?
CAG
You are a doctor tased with diagnosing a patient that comes to you with mental impairment. Upon performing genetic tests, you find he has approximately 300 repeats of GCC in one of his genes. His father and grandfather had similar mental impairment but were never diagnosed with a condition prior to their death. His grandmother, mother and sisters are unaffected. What disease do you predict that this patient has?
FRAXE
The term that refers to the linkage of alleles or molecular markers along a single chromosome is?
Halotype
which technique can be used at the earliest stage in a pregnancy to provide a sample for fetal genetic testing?
chronic vllus sampling
The process of _____ removes amniotic fluid from a pregnant mother to examine fetal cells for genetic problems?
amniocentesis
In the analysis of a family, you notice that males are more likely to contract a certain disease and the daughters of affected males produce 50% of their sons affected with the disease. The disease is displaying which of the following patterns of inheritance?
X-linked recessive
Which of the following is typically associated with an autosomal recessive pattern of inheritance?
An affected offspring has two unaffected patterns
A gene that promotes the development of cancer when it sustains a gain-of-function mutations is called a
proto-oncogene
The term that indicates the cancer has begun to migrate to other parts of the body is ____
metastatic
An example of personalized medicine would be
determining the CYP2CP alleles present to help set the patient’s coumarin dose
Epigenetics may play a role in cancer by
causing a change in gene expression patterns
Capases are active during which of the following
apoptosis
The scientist _____ developed a novel method to synthesize RNA. Short RNAs of 2 to 4 nucleotides were linked together to create a copolymer. The resulting peptide created after translation revelaed the 3-letter code for the amino acids
Khorana and colleagues
You perform a cell-free translation experiment like Nirenberg and Matthaei. You start with 60% C and 40% A. What relative amount of radilabeled proline do you expect in the translated polypeptides?
36%
Where are the ribosomal subunits assembled?
nucleolus
Which component of the ribosomes is part of the peptidyl transferase in the 50S subunit and acts as a ribozyme to catalyze peptide bond formation?
23S rRNA
In bacteria, the sequence that facilitates the binding of the mRNA to the ribosome is called the
Shine-Dalgarno sequence
What site does the initiator tRNA bind to on the ribosome
P
What is the least number of tRNAs that can be used to recognize all of the codons of isoleucine and waht is/are the anticodon(s)
one - 5’ IAU 3’
Which molecule contains an anticodon?
tRNA
You are studying the DNA of a person who you know has two defective copies of the gene that encodes phenylalanine hydroxylase. You are surprised to find that this person also carries two defective copies of the gene for homogentisic acid oxidase. What disease symptoms will this person exhibit? (Assume pathway intermediates are not available from sources outside the phenylalanine breakdown pathway.)
This person will exhibit symptoms of phenylketonuria
The C-terminus of a polypeptide always contains
A carboxyl group
Regulation of gene expression may occur at which of the following levels?
Transcription
Translation
Post-translation
Riboswitches have been shown to affect regulation of
transcription and translation
If a bacterium is placed in an environment that contains both glucose and lactose, the regulation of the lac operon will allow which nutrient to be processed first?
glucose
a deletion in an operon removes the promoter. How will that affect the transcript that is produced from the operon?
the transcript will not be produced
Which of the following is found in an operon
Promoter
Terminator
Two or more genes
Operator
What is the gene responsible for attenuation in the trp operon?
trpL
What would be the result if the U-rich sequence after the fourth stem loop in the trp operon was replaced by a UG-rich sequence?
Attenuation would not occur if tryptophan was high
In a particular E. coli strain, a mutation in the thiMD operon results in improper formation of the stem loop secondary structure making it impossible to bind TPP. There are two enzymes encoded by the thiMD operon. How many of the enzymes encoded in the thiMD operon are translated?
two
Antisense RNA does which of the following
binds to complementary RNA and prevents its translation
Which of the following is not an example of translation regulation in prokaryotes
Phosphorylation of an enzyme
A particular gene has a mutation in its NFR that causes it to bind abnormally tightly to histones. What effect would you expect this mutation has on the expression of this gene?
The expression of the gene would be abnormally low or absent
Gene methylation can be detected through the use of restriction endonuclease. Usually there are used in pairs. where one enzyme will digest only unmethylated DNA in its recognition sequence while the other is insensitive to methylation. Which of the following statements is correct?
The enzyme that is insensitive to methylation serves as a control to make sure the inability of the other enzyme to digest DNA is not due to a mutation
What is the difference between the trithorax (TrxG) and polycomb (PcG) complexes of proteins
TrxG complex proteins activate gene expression by methylation lysine 4 on H3, while PcG complex proteins repress gene expression by methylating lysine 27 on H3
Which of the following is part of the process of X-chromosome inactivation?
Binding of multiple Xist transcripts to Xic on the X chromosome that will be inactivated
The Avy allele of the Agouti gene involves the insertion of a transposable element upstream from the normal Agouti promoter. The transposable element carries a promoter that causes the overexpression of the Agouti gene. Mice carrying this allele tend to have coat colors that are more yellow than mice that don’t have this transposable element. If pregnant female mice are fed a diet that contains chemicals that inhibit DNA methylation, how would you expect that this diet would affect the coat color of offspring carrying the Avy allele?
Their fur would be more yellow because of the Agouti gene that would tend to be over expressed
Regions of the chromatin that are more compacted are called ____; they are usually found _____ in the nucleus
heterochromatin, at the periphery
Which of the following is an example of epigenetic inheritance?
Expression of the Igf2 gene based on methylation of the ICR and DMR regions
What effect will a mutation in IRP that prevents it from bidning to iron have on individual?
There will be excess transferrin, so iron intake must be lowered
Which DNA sequence would also work in place of the following bi-directional enhancer
5’ GTTC 3’
3’ CAAG 5’
5’ GAAC 3’
3’ CTTG 5’
What would be the result of a mutation in HSP90 that prevented its binding to the glucocorticoid receptor?
Expression of the regulated genes would become constitutive
