Question 1

What are enhancers?

Accepted Answer

Enhancers are DNA sequences that typically have binding sites for several different activators and repressors.They are located somewhere in the vicinity of the gene,much farther away than promoter sequences,sometimes tens of kilobases away.They allow complex and nuanced control of gene expression depending on a number of different conditions such as developmental stage,tissue type,and response to extracellular signals.

Question 2

The protein class(es)involved in the activation of transcription is (are)

Accepted Answer

A) general transcription factors (GTFs). 
B) transactivators. 
C) coactivators. 
D) A and B only 
E) A,B,and C 
A) general transcription factors (GTFs). 
B) transactivators. 
C) coactivators. 
D) A and B only 
E) A,B,and C E

Question 3

Transcriptionally active genes show lower levels of DNA methylation compared with transcriptionally inactive genes.

Accepted Answer

A) True 
 B)False  True

Question 4

In eukaryotic cells,steroid hormones

Accepted Answer

A) bind to cytoplasmic receptors,are transported to the nucleus,bind DNA,and regulate gene expression. 
B) bind to cell surface receptors and send signals that result in regulation of genes in the nucleus. 
C) act as enhancers and bind to an assortment of activators and repressors. 
D) methylate DNA to regulate gene expression. 
E) cause maternal effect. 
A) bind to cytoplasmic receptors,are transported to the nucleus,bind DNA,and regulate gene expression. 
B) bind to cell surface receptors and send signals that result in regulation of genes in the nucleus. 
C) act as enhancers and bind to an assortment of activators and repressors. 
D) methylate DNA to regulate gene expression. 
E) cause maternal effect.

Question 5

Noncoding RNAs called mRNAs are present in most eukaryote genomes and are involved in negatively regulating gene expression through degradation of mRNAs with complementary sequences.

Accepted Answer

A) True 
 B)False

Question 6

In genetic imprinting,expression depends on the parent of origin of a given allele.How might imprinting affect the expression of a hypothetical autosomal disease that expresses in dominant fashion and recessive fashion,and how might imprinting be detected?

Accepted Answer

In individuals heterozygous for the domi

Question 7

Unlike bacterial operons,eukaryotic operons

Accepted Answer

A) are all positively controlled. 
B) are all negatively controlled. 
C) are restricted to certain eukaryotic kingdoms. 
D) are exceedingly rare. 
E) None of these 
A) are all positively controlled. 
B) are all negatively controlled. 
C) are restricted to certain eukaryotic kingdoms. 
D) are exceedingly rare. 
E) None of these

Question 8

Some genes that are expressed in the fetal stage are never expressed again in that individual's life.What do you think is the most common mechanism for preventing the expression of such genes?

Accepted Answer

Such genes are permanently sil

Question 9

Match between columns
                        Premises: Produces more than one protein from one gene
Gene regulation dependant on parent of origin
Controls transcription initiation
A method for targeting RNAs for degradation
A method of targeting proteins for degradation

Accepted Answer

The Answer of Ubiquitination and Enhancer and siRNA and Alternative is...

Question 10

Gene silencing in eukaryotes is often achieved through chromatin structure.

Accepted Answer

A) True 
 B)False

Question 11

Activators in eukaryotes

Accepted Answer

A) bind to enhancers. 
B) may act as monomers 
C) may act as homodimers. 
D) may act as heterodimers with a DNA binding subunit and an activation subunit. 
E) All of these 
A) bind to enhancers. 
B) may act as monomers 
C) may act as homodimers. 
D) may act as heterodimers with a DNA binding subunit and an activation subunit. 
E) All of these

Question 12

What essential difference between the growth and reproductive strategies of prokaryotes and multicellular eukaryotes explains why the latter have far more sophisticated regulatory mechanisms?

Accepted Answer

An important point made in this chapter

Question 13

Evolutionary biologists suspect that genetic imprinting evolved through parent-offspring conflict.What kinds of "conflict of interest" in progeny development can you imagine between mammalian parents?

Accepted Answer

Fetal development requires enormous ener

Question 14

Describe the use of the DNA-degrading enzyme DNase I in experiments that explore the effect of chromatin on gene inactivation.

Accepted Answer

DNA from cells with certain transcriptio

Question 15

Heterochromatin is associated with

Accepted Answer

A) differential gene expression. 
B) gene silencing. 
C) mRNA translation. 
D) heterozygotes. 
E) A,B,and C only 
A) differential gene expression. 
B) gene silencing. 
C) mRNA translation. 
D) heterozygotes. 
E) A,B,and C only

Question 16

Change in the DNA-histone complex that can increase or decrease transcriptional activity is termed

Accepted Answer

A) induction. 
B) gene regulation. 
C) chromatin remodeling. 
D) nucleosome formation. 
E) None of these 
A) induction. 
B) gene regulation. 
C) chromatin remodeling. 
D) nucleosome formation. 
E) None of these

Question 17

Eukaryotic repression generally occurs via physical blockage of the promoter.

Accepted Answer

A) True 
 B)False

Question 18

RNA silencing involves

Accepted Answer

A) miRNAs. 
B) siRNAs. 
C) double-stranded RNA. 
D) a protein called Dicer. 
E) All of these 
A) miRNAs. 
B) siRNAs. 
C) double-stranded RNA. 
D) a protein called Dicer. 
E) All of these

Question 19

Interference RNA technology is one of the most exciting new developments in genetics in recent years.In April 2004,Cancer Research UK and the Netherlands Cancer Institute announced creation of a 24,000-molecule iRNA library,designed to inactivate about 8,000 human genes.One hope for this library is its application in combating cancer.How might iRNA be implemented in cancer treatment?

Accepted Answer

Cancers for which the genetic basis is u

Question 20

Recombinases mediate transcript processing from pre-mRNA to mature mRNA.

Accepted Answer

A) True 
 B)False

Exam 18: Regulation of Gene Expression in Eukaryotes

What are enhancers?

The protein class(es)involved in the activation of transcription is (are)

Transcriptionally active genes show lower levels of DNA methylation compared with transcriptionally inactive genes.

In eukaryotic cells,steroid hormones

Noncoding RNAs called mRNAs are present in most eukaryote genomes and are involved in negatively regulating gene expression through degradation of mRNAs with complementary sequences.

In genetic imprinting,expression depends on the parent of origin of a given allele.How might imprinting affect the expression of a hypothetical autosomal disease that expresses in dominant fashion and recessive fashion,and how might imprinting be detected?

Unlike bacterial operons,eukaryotic operons

Some genes that are expressed in the fetal stage are never expressed again in that individual's life.What do you think is the most common mechanism for preventing the expression of such genes?

Gene silencing in eukaryotes is often achieved through chromatin structure.

Activators in eukaryotes

What essential difference between the growth and reproductive strategies of prokaryotes and multicellular eukaryotes explains why the latter have far more sophisticated regulatory mechanisms?

Evolutionary biologists suspect that genetic imprinting evolved through parent-offspring conflict.What kinds of "conflict of interest" in progeny development can you imagine between mammalian parents?

Describe the use of the DNA-degrading enzyme DNase I in experiments that explore the effect of chromatin on gene inactivation.

Heterochromatin is associated with

Change in the DNA-histone complex that can increase or decrease transcriptional activity is termed

Eukaryotic repression generally occurs via physical blockage of the promoter.

RNA silencing involves

Recombinases mediate transcript processing from pre-mRNA to mature mRNA.

Genetics: An Introduction

DNA: The Genetic Material

DNA Replication

Gene Function

Gene Expression: Transcription

Gene Expression: Translation

Dna Mutation, DNA Repair, and Transposable Elements

Genomics: The Mapping and Sequencing of Genomes

Functional and Comparative Genomics

Recombinant DNA Technology

Mendelian Genetics

Chromosomal Basis of Inheritance

Extensions of and Deviations From Mendelian Genetic Principles

Genetic Mapping in Eukaryotes

Genetics of Bacteria and Bacteriophages

Variations in Chromosome Structure and Number

Regulation of Gene Expression in Bacteria and Bacteriophages

Genetic Analysis of Development

Genetics of Cancer

Population Genetics

Quantitative Genetics

Molecular Evolution

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