Genetics Ch.17, 19, 22 Quiz Questions
How does position effect influence gene expression?
1). 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 2). The movement of the gene may place it into a region that is highly condensed 3).The movement of a gene may remove it from its normal promoter, thus silencing the gene.
Which of the following statements are correct?
1).Environmental epigenetic changes can vary due to the exposure of the organism to different environmental conditions, while those programmed during development are the result of stimuli generated by the organism itself.
For a single-gene disorder, the concordance among monozygotic twins should be
100%
For a recessive single-gene disorder, the concordance among dizygotic twins should be
25%
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?
3.3E-5
Which of the following is an example of a base analog?
5BU
Where is the IRE located in the regulation of ferritin translation?
5′ end of mRNA
A translocation that moves a gene from an area of euchromatin to heterochromatin would typically cause _____ in the expression of the gene.
A reduction
The process of _______ removes amniotic fluid from a pregnant mother to examine fetal cells for genetic problems.
Amniocentesis
What gene(s) is/are encoded in the Xic?
Both the Tsix and Xist are genes are in the Xic region
Mutations that change the configuration of a protein at a specific temperature are called ____ mutations.
Conditional
In cancer cells, one allele of a tumor suppressor gene called p53 is frequently mutated so that the protein is inactive, not produced, or deleted. The other allele usually has a normal sequence, and the promoter remains intact, but the gene is not expressed. Sequencing with sodium bisulfite modification of DNA can be used to detect which cytosines are methylated. If cancer cell DNA is sequenced, which of the following results would be expected?
Cytosines in or near the promoter region will be methylated.
You are working in a lab where you are studying a disease that is known to be caused by a single nucleotide change, although the effect this change ultimately has on the protein's structure/function is unknown. You have DNA samples from multiple patients that you suspect of having this disease. What is the most efficient way to test the samples for the relevant mutation?
DNA sequencing
The conversion of cytosine to uracil in DNA is an example of _____.
Deamination
An example of personalized medicine would be
Determining the CYP2C9 alleles present to help set the patients coumarin dose.
Which of the following are molecular mechanisms used in epigenetic gene regulation?
Dna Methylation, Covalent Histone modification, Chromatin Remodeling
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.
What is the difference between genetic testing and genetic screening?
Genetic testing is concerned more with individuals and genetic screening is concerned with populations.
The differentially methylated region (DMR) is associated with which of the following
Genomic imprinting.
Regions of chromatin that are more compact are called __________; they are usually found __________ in the nucleus.
Heterochromatin; at the periphery
What are histone variants?
Histone proteins that have slightly different amino acid sequences and have specialized functions.
Most genes imprinted by methylation are silenced. What is one exception to this rule?
Igf2
In humans, a recent study has shown that maternal anxiety during pregnancy can diminish the methylation of the ICR located between the H19 and Igf2 genes of the embryo and fetus. How would this affect the expression of the maternal and paternal alleles of the Igf2 gene after the baby is born?
It would not affect the expression of the maternal allele, but the paternal allele would be inhibited.
The term that indicates that cancer has begun to migrate to other parts of the body is ______.
Metastatic
Which DNA repair process utilizes MutL, MutH, and MutS proteins in E. coli?
Mismatch repair
Translocations and inversions may cause which of the following?
Position effect
What general transcription factor is most often affected by regulatory transcription factors?
TFIID
Gene methylation can be detected through the use of restriction endonucleases. Usually these 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.
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.
Locus heterogeneity can cause difficulties in pedigree analysis since
The inheritance of more than one gene is being analyzed
A queen bee is larger than the female worker bees in a hive. The queen develops functional ovaries that allow her to produce up to 2000 eggs a day. What determines which bees become queen bees?
The larvae raised on a diet of royal jelly.
Following mitosis, the two daughter cells usually have __________ pattern of facultative heterochromatin and __________ pattern of constitutive heterochromatin as was present in the mother cell.
The same; the same
How would a mutation that increases the rate of GTP hydrolysis by the Ras protein affect the EGF signaling pathway and how would it affect cell growth?
The signaling pathway would be turned off faster and cell growth would be inhibited.
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 increase DNA methylation, how would you expect that this diet would affect the coat color of offspring carrying the Avy allele?
Their fur would be less yellow (darker brown) because the Agouti gene would tend to be under expressed.
Genome wide association studies are used __________.
To identify single nucleotide polymorphisms that are near disease causing genes.
What would be a set of anticipated results from a "Lederberg" experiment?
Total number of colonies on plate: 1500. Total number of resistant colonies on replica plate with T1: 15
What are the general ways that tumor suppressors and oncogenes act?
Tumor suppressors inhibit the cell cycle and oncogenes stimulate the cell cycle.
In the nucleotide excision repair system, which of the following proteins is responsible for recognizing a thymine dimer to be repaired?
UvrA/UvrB
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. This disease is displaying which of the following patterns of inheritance?
X-linked recessive
A temporary change in the structure of a nitrogenous base is called ______.
a tautomeric shift
Which of the following integrate into the double-helix of DNA, interfering with DNA replication?
acridine dyes
Epigenetics may play a role in cancer by
causing a change in gene expression patterns
The complete loss of either a guanine or adenine from DNA is an example of _____.
depurination
The term that refers to the linkage of alleles or molecular markers along a single chromosome is
haplotype
What kind of mutation would be expected both within oncogenes and tumor suppressor genes that would result in gain-of-function or loss-of-function, respectively?
missense
The results of the replica plating experiments by the Lederbergs supported which of the following theories?
random mutation theory
Combinatorial factors include activators and repressors as well as
small effector molecules, proteins that alter the composition of nucleosomes, and DNA methylation.