Question 1

What gene is most responsible for X-chromosome inactivation?

Accepted Answer

A)  Xic 
B)  Xist 
C)  Tsix 
D)  Xce 
A)  Xic 
B)  Xist 
C)  Tsix 
D)  Xce

Question 2

Genomic imprinting is a result of

Accepted Answer

A)  nucleosome location. 
B)  histone activation. 
C)  DNA methylation. 
D)  serine to leucine changes in the genetic code. 
A)  nucleosome location. 
B)  histone activation. 
C)  DNA methylation. 
D)  serine to leucine changes in the genetic code.

Question 3

What is the molecular mechanism for imprinting a gene?

Accepted Answer

A)  Acetylation 
B)  Nitration 
C)  Phosphorylation 
D)  Methylation 
A)  Acetylation 
B)  Nitration 
C)  Phosphorylation 
D)  Methylation

Question 4

Both parents usually imprint the same gene.

Accepted Answer

A) True 
 B)False

Question 5

What general transcription factor is most often affected by regulatory transcription factors?

Accepted Answer

A)  TFIIB 
B)  TFIID 
C)  TFIIE 
D)  TFIIF 
A)  TFIIB 
B)  TFIID 
C)  TFIIE 
D)  TFIIF

Question 6

Acetylation of histones results in

Accepted Answer

A)  formation of an open chromatin structure. 
B)  removal of histones from the histone octomer. 
C)  formation of a closed chromatin structure. 
D)  termination of transcription. 
A)  formation of an open chromatin structure. 
B)  removal of histones from the histone octomer. 
C)  formation of a closed chromatin structure. 
D)  termination of transcription.

Question 7

Steroid hormones are an example of an effector which regulates regulatory transcription factor activity.

Accepted Answer

A) True 
 B)False

Question 8

What is the difference between the trithorax (TrxG)and polycomb (PcG)complexes of proteins?

Accepted Answer

A)  TrxG proteins methylate lysine 27 on histone H3 while PcG complexes methylate lysine 4 on H3 
B)  Methylation of lysine at position 4 on H3 results in silencing of gene expression 
C)  TrxG complex proteins activate gene expression by methylating lysine 4 on H3, while PcG complex proteins repress gene expression by methylating lysine 27 on H3. 
D)  Methylation of H3 on lysine 27 can result in activation of transcription 
A)  TrxG proteins methylate lysine 27 on histone H3 while PcG complexes methylate lysine 4 on H3 
B)  Methylation of lysine at position 4 on H3 results in silencing of gene expression 
C)  TrxG complex proteins activate gene expression by methylating lysine 4 on H3, while PcG complex proteins repress gene expression by methylating lysine 27 on H3. 
D)  Methylation of H3 on lysine 27 can result in activation of transcription

Question 9

What gene(s)is/are encoded in the Xic?

Accepted Answer

A)  Xce 
B)  Xist 
C)  Tsix 
D)  Both the Tsix and Xist are genes are in the Xic region 
A)  Xce 
B)  Xist 
C)  Tsix 
D)  Both the Tsix and Xist are genes are in the Xic region

Question 10

Which of the following is an example of epigenetic inheritance?

Accepted Answer

A)  Expression of the Igf2 gene based on methylation of the ICR and DMR regions 
B)  Inheritance of flower color as studied by Mendel 
C)  Control of mRNA stability by an RNA-binding protein 
D)  Activation of transcription by a general transcription factor 
A)  Expression of the Igf2 gene based on methylation of the ICR and DMR regions 
B)  Inheritance of flower color as studied by Mendel 
C)  Control of mRNA stability by an RNA-binding protein 
D)  Activation of transcription by a general transcription factor

Question 11

Where is the IRE located in the ferritin gene?

Accepted Answer

A)  5′ end of DNA 
B)  5′ end of mRNA 
C)  3′ end of DNA 
D)  3′ end of mRNA 
A)  5′ end of DNA 
B)  5′ end of mRNA 
C)  3′ end of DNA 
D)  3′ end of mRNA

Question 12

Which of the following is part of the mechanism for epigenetic regulation of the Igf2 gene?

Accepted Answer

A)  Methylation of the H19 locus 
B)  Methylation of the ICR and DMR domains 
C)  Binding of CTC factors to methylated sequences 
A)  Methylation of the H19 locus 
B)  Methylation of the ICR and DMR domains 
C)  Binding of CTC factors to methylated sequences

Question 13

What is a major difference between the general and regulatory transcription factors?

Accepted Answer

A)  General transcription factors only regulate the housekeeping genes while regulatory transcription factors control all of the other genes. 
B)  General transcription factors are essential for any transcription for all genes while regulatory transcription factors regulate transcription of specific genes. 
C)  General transcription factors act as heterodimers while regulatory transcription factors act as monomers. 
D)  General transcription factors regulate basal genes while regulatory transcription factors control all of the other genes. 
A)  General transcription factors only regulate the housekeeping genes while regulatory transcription factors control all of the other genes. 
B)  General transcription factors are essential for any transcription for all genes while regulatory transcription factors regulate transcription of specific genes. 
C)  General transcription factors act as heterodimers while regulatory transcription factors act as monomers. 
D)  General transcription factors regulate basal genes while regulatory transcription factors control all of the other genes.

Question 14

Vernalization in Arabidopsis involves epigenetic changes as cold temperatures induce histone modifications that influence expression of genes for germination or flowering in the spring when temperatures increase.

Accepted Answer

A) True 
 B)False

Question 15

In the regulation of Igf2,it is possible that the effects of the association of the ICR and DMR regions with the CTC factors could be distance dependent. An experiment could be devised in which the distances between these regions could be varied and the rates of transcription could be measured. The graph shows some possible results. Which letter represents the most likely outcome if increasing the distance between ICR and DMR does not greatly enhance transcription until a critical distance is reached?

Accepted Answer

A)  A 
B)  B 
C)  C 
D)  D 
A)  A 
B)  B 
C)  C 
D)  D

Question 16

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?

Accepted Answer

A)  Cytosines in or near the promoter region will be methylated 
B)  Cytosines in or near the promoter will not be methylated 
C)  Cytosines in the coding region will have an increased methylation 
D)  There will be no differences in the methylation pattern of the promoter of p53 from a cancer cell and a normal cell 
A)  Cytosines in or near the promoter region will be methylated 
B)  Cytosines in or near the promoter will not be methylated 
C)  Cytosines in the coding region will have an increased methylation 
D)  There will be no differences in the methylation pattern of the promoter of p53 from a cancer cell and a normal cell

Question 17

DNA that contains actively transcribed genes would most likely contain chromatin in the closed configuration.

Accepted Answer

A) True 
 B)False

Question 18

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?

Accepted Answer

A)  A single dominant allele of the Queen gene 
B)  The larvae raised on a diet of royal jelly 
C)  The larvae raised on a diet of pollen and nectar 
D)  The egg that hatches first 
A)  A single dominant allele of the Queen gene 
B)  The larvae raised on a diet of royal jelly 
C)  The larvae raised on a diet of pollen and nectar 
D)  The egg that hatches first

Question 19

In imprinting of the Igf2 gene in mice,are the ICR and DMR methylated on the maternal or paternal chromosome? Which chromosome expresses Igf2?

Accepted Answer

A)  Paternal, paternal 
B)  Paternal, maternal 
C)  Maternal, paternal 
D)  Maternal, maternal 
A)  Paternal, paternal 
B)  Paternal, maternal 
C)  Maternal, paternal 
D)  Maternal, maternal

Question 20

How many Barr bodies would an individual with a XXY genotype possess?

Accepted Answer

A)  0 
B)  1 
C)  2 
D)  None of the answers are correct. 
A)  0 
B)  1 
C)  2 
D)  None of the answers are correct.

Exam 17: Gene Regulation in Eukaryotes

What gene is most responsible for X-chromosome inactivation?

Genomic imprinting is a result of

What is the molecular mechanism for imprinting a gene?

Both parents usually imprint the same gene.

What general transcription factor is most often affected by regulatory transcription factors?

Acetylation of histones results in

Steroid hormones are an example of an effector which regulates regulatory transcription factor activity.

What is the difference between the trithorax (TrxG)and polycomb (PcG)complexes of proteins?

What gene(s)is/are encoded in the Xic?

Which of the following is an example of epigenetic inheritance?

Where is the IRE located in the ferritin gene?

Which of the following is part of the mechanism for epigenetic regulation of the Igf2 gene?

What is a major difference between the general and regulatory transcription factors?

Vernalization in Arabidopsis involves epigenetic changes as cold temperatures induce histone modifications that influence expression of genes for germination or flowering in the spring when temperatures increase.

DNA that contains actively transcribed genes would most likely contain chromatin in the closed configuration.

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?

In imprinting of the Igf2 gene in mice,are the ICR and DMR methylated on the maternal or paternal chromosome? Which chromosome expresses Igf2?

How many Barr bodies would an individual with a XXY genotype possess?

Overview of Genetics

Reproduction and Chromosome Transmission

Mendelian Inheritance

Sex Determination and Sex Chromosomes

Extensions of Mendelian Inheritance

Extranuclear Inheritance, Imprinting, and Maternal Effect

Genetic Linkage and Mapping in Eukaryotes

Variation in Chromosome Structure and Number

Genetics in Bacteria

Genetics of Viruses

Molecular Structure of DNA and RNA

Molecular Structure of Chromosomes and Transposition

Dna Replication and Recombination

Gene Transcription and RNA Modification

Translation of MRNA

Gene Regulation in Bacteria

Non-Coding Rnas

Gene Mutation and DNA Repair

Molecular Technologies

Genomics

Medical Genetics and Cancer

Population Genetics

Quantitative Genetics

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