Question 1

A cell can form 10-nm chromatin fibers,but not 30-nm fibers.Which molecule has likely been removed or mutated in this cell?

Accepted Answer

A) H1 
B) H2A 
C) H3 
D) topoisomerase 
E) SMC proteins 
A) H1 
B) H2A 
C) H3 
D) topoisomerase 
E) SMC proteins A

Question 2

The flies with variegated eye color had what abnormal chromosome structure?

Accepted Answer

A) X-chromosome inversion that moves the w⁺ gene to a different orientation on the chromosome in some cells following x-ray exposure 
B) X-chromosome translocation that moves the w⁺ gene to a region of heterochromatin on another chromosome in some cells following x-ray exposure 
C) a mutation in the w⁺ gene following x-ray exposure that causes the gene to be overexpressed in a tissue-specific manner 
D) X-chromosome deletion that deleted the w⁺ gene in some cells following x-ray exposure 
E) a mutation in a somatic chromosome that causes the w⁺ gene to be translocated to the X-chromosomes following x-ray exposure 
A) X-chromosome inversion that moves the w⁺ gene to a different orientation on the chromosome in some cells following x-ray exposure 
B) X-chromosome translocation that moves the w⁺ gene to a region of heterochromatin on another chromosome in some cells following x-ray exposure 
C) a mutation in the w⁺ gene following x-ray exposure that causes the gene to be overexpressed in a tissue-specific manner 
D) X-chromosome deletion that deleted the w⁺ gene in some cells following x-ray exposure 
E) a mutation in a somatic chromosome that causes the w⁺ gene to be translocated to the X-chromosomes following x-ray exposure A

Question 3

What is the name of the structure formed when the 10-nm fibers of chromatin form a cylindrical filament of coiled nucleosomes?

Accepted Answer

solenoid structure

Question 4

Eukaryotic chromosomes are a combination of proteins and DNA,which allows the cell to perform which four essential functions?

Accepted Answer

1.compacts the DNA so it can fit in the

Question 5

You are trying to prepare a DNA karyotype,but this time you forgot to add trypsin to your chromosome preparation.What effect would you expect to see?

Accepted Answer

A) Dyes would stain the chromosomes darker because more proteins are present to take up the dye. 
B) Dyes would not stain the chromosomes as expected,because proteins would not be removed from the chromatin and so would block the dye from accessing the DNA. 
C) Chromosomes do not condense properly,so it would be very difficult to isolate individual chromosomes. 
D) Chromosomes would be degraded quickly because the trypsin is necessary to promote DNA stability by adding more scaffold proteins to the chromatin. 
E) The chromosomes would be more difficult to pair up because the trypsin acts as a dye,creating a banding pattern that distinguishes between chromosomes. 
A) Dyes would stain the chromosomes darker because more proteins are present to take up the dye. 
B) Dyes would not stain the chromosomes as expected,because proteins would not be removed from the chromatin and so would block the dye from accessing the DNA. 
C) Chromosomes do not condense properly,so it would be very difficult to isolate individual chromosomes. 
D) Chromosomes would be degraded quickly because the trypsin is necessary to promote DNA stability by adding more scaffold proteins to the chromatin. 
E) The chromosomes would be more difficult to pair up because the trypsin acts as a dye,creating a banding pattern that distinguishes between chromosomes.

Question 6

Karyotypes are a method for displaying chromosomes by grouping them into homologous pairs based on what two distinguishing factors?

Accepted Answer

size and b

Question 7

What technique would you use to detect a target sequence in an intact chromosome using a labeled molecular probe?

Accepted Answer

A) PCR 
B) in situ hybridization 
C) western blotting 
D) Sanger sequencing 
E) karyotyping 
A) PCR 
B) in situ hybridization 
C) western blotting 
D) Sanger sequencing 
E) karyotyping

Question 8

Typically,acetylation of histone tails leads to

Accepted Answer

A) removal of the protein components of the chromatin from the DNA. 
B) relaxed packaging of the chromatin and increased transcription. 
C) tighter packaging of the chromatin and reduced transcription. 
D) increased amounts of euchromatin relative to heterochromatin. 
E) activation of topoisomerase. 
A) removal of the protein components of the chromatin from the DNA. 
B) relaxed packaging of the chromatin and increased transcription. 
C) tighter packaging of the chromatin and reduced transcription. 
D) increased amounts of euchromatin relative to heterochromatin. 
E) activation of topoisomerase.

Question 9

The DNA-protein complex that comprises eukaryotic chromosomes is called ________.

Accepted Answer

The answer of The DNA-protein complex that comprises eukaryotic chromosomes...

Question 10

What is the function of interchromosomal domains in gene transcription?

Accepted Answer

A) These domains separate chromosome territories and are areas of active transcription. 
B) These domains act as regions for formation of chiasmata during crossing over. 
C) These domains act as gene-rich regions positioned toward the nuclear membrane to maximize gene transcription. 
D) These domains contain no chromatin and act as channels for the movement of proteins,RNAs,and enzymes among the chromosomal territories. 
E) These domains act as the regions of the chromosome recognized during meiosis when homologous chromosomes are matched up and aligned at the metaphase I plate. 
A) These domains separate chromosome territories and are areas of active transcription. 
B) These domains act as regions for formation of chiasmata during crossing over. 
C) These domains act as gene-rich regions positioned toward the nuclear membrane to maximize gene transcription. 
D) These domains contain no chromatin and act as channels for the movement of proteins,RNAs,and enzymes among the chromosomal territories. 
E) These domains act as the regions of the chromosome recognized during meiosis when homologous chromosomes are matched up and aligned at the metaphase I plate.

Question 11

If you block histone deacetylase,what effect would you expect to see on transcriptional activity?

Accepted Answer

continued/

Question 12

What type of DNA supercoiling is the most common?

Accepted Answer

The answer of What type of DNA supercoiling is the...

Question 13

You have isolated DNA from actively replicating cells.Where would you expect to find this DNA on a gel?

Accepted Answer

A) DNA would be highly supercoiled and would be found in the band seen in the positive pole (bottom)of Lane 1. 
B) DNA would be predominantly relaxed and would be found in the band seen in the positive pole (bottom)of Lane 1. 
C) DNA would be highly supercoiled and would be found in the band seen in the negative pole (top)of Lane 1. 
D) DNA would be predominantly relaxed and would be found in the band seen in the negative pole (top)of Lane 1. 
E) DNA would be both relaxed and supercoiled,so it would appear in a pattern similar to Lane 2. 
A) DNA would be highly supercoiled and would be found in the band seen in the positive pole (bottom)of Lane 1. 
B) DNA would be predominantly relaxed and would be found in the band seen in the positive pole (bottom)of Lane 1. 
C) DNA would be highly supercoiled and would be found in the band seen in the negative pole (top)of Lane 1. 
D) DNA would be predominantly relaxed and would be found in the band seen in the negative pole (top)of Lane 1. 
E) DNA would be both relaxed and supercoiled,so it would appear in a pattern similar to Lane 2.

Question 14

Nucleosomes are comprised of how many molecules of histones?

Accepted Answer

The answer of Nucleosomes are comprised of how many molecules...

Question 15

Tortoiseshell cats have a coat-color gene on their X chromosome.What process in eukaryotes explains why males can have solid orange or black fur,and only females can have the tortoiseshell pattern of fur?

Accepted Answer

The gene encoding coat color is X-linked

Question 16

Which proteins would you target if you wanted to disrupt the chromosome superstructure for chromatin condensation that ultimately produces the characteristic shape of the metaphase chromosome?

Accepted Answer

The answer of Which proteins would you target if you...

Question 17

Which type of chromosome has no p arms?

Accepted Answer

A) metacentric 
B) submetacentric 
C) acrocentric 
D) subacrocentric 
E) telocentric 
A) metacentric 
B) submetacentric 
C) acrocentric 
D) subacrocentric 
E) telocentric

Question 18

What gene is critical for establishment of X-inactivation in mammals?

Accepted Answer

The answer of What gene is critical for establishment of...

Question 19

Active transcription occurs in regions of chromatin loops that are located

Accepted Answer

A) near the MARS. 
B) a large distance away from the MARS. 
C) within the linker DNA. 
D) within the telomeres. 
E) within the euchromatin and constitutive heterochromatin. 
A) near the MARS. 
B) a large distance away from the MARS. 
C) within the linker DNA. 
D) within the telomeres. 
E) within the euchromatin and constitutive heterochromatin.

Question 20

Under normal cellular conditions,what is the diameter of the chromatin as it forms the solenoid structure?

Accepted Answer

A) 3 nm 
B) 10 nm 
C) 30 nm 
D) 34 nm 
E) 100 nm 
A) 3 nm 
B) 10 nm 
C) 30 nm 
D) 34 nm 
E) 100 nm

Exam 11: Chromosome Structure

A cell can form 10-nm chromatin fibers,but not 30-nm fibers.Which molecule has likely been removed or mutated in this cell?

The flies with variegated eye color had what abnormal chromosome structure?

What is the name of the structure formed when the 10-nm fibers of chromatin form a cylindrical filament of coiled nucleosomes?

Eukaryotic chromosomes are a combination of proteins and DNA,which allows the cell to perform which four essential functions?

You are trying to prepare a DNA karyotype,but this time you forgot to add trypsin to your chromosome preparation.What effect would you expect to see?

Karyotypes are a method for displaying chromosomes by grouping them into homologous pairs based on what two distinguishing factors?

What technique would you use to detect a target sequence in an intact chromosome using a labeled molecular probe?

Typically,acetylation of histone tails leads to

The DNA-protein complex that comprises eukaryotic chromosomes is called ________.

What is the function of interchromosomal domains in gene transcription?

If you block histone deacetylase,what effect would you expect to see on transcriptional activity?

What type of DNA supercoiling is the most common?

You have isolated DNA from actively replicating cells.Where would you expect to find this DNA on a gel?

Nucleosomes are comprised of how many molecules of histones?

Tortoiseshell cats have a coat-color gene on their X chromosome.What process in eukaryotes explains why males can have solid orange or black fur,and only females can have the tortoiseshell pattern of fur?

Which proteins would you target if you wanted to disrupt the chromosome superstructure for chromatin condensation that ultimately produces the characteristic shape of the metaphase chromosome?

Which type of chromosome has no p arms?

What gene is critical for establishment of X-inactivation in mammals?

Active transcription occurs in regions of chromatin loops that are located

Under normal cellular conditions,what is the diameter of the chromatin as it forms the solenoid structure?

The Molecular Basis of Heredity, Variation, and Evolution

Transmission Genetics

Cell Division and Chromosome Heredity

Gene Interaction

Genetic Linkage and Mapping in Eukaryotes

Genetic Analysis and Mapping in Bacteria and Bacteriophage

DNA Structure and Replication

Molecular Biology and Transcription and Rna Processing

The Molecular Biology of Translation

The Integration of Genetic Approaches: Understanding Sickle Cell Disease

Gene Mutation, DNA Repair, and Homologous Recombination

Chromosome Aberrations and Transposition

Regulation of Gene Expression in Bacteria and Bacteriophage

Regulation of Gene Expression in Eukaryotes

Forward Genetics and Recombinant DNA Technology

Applications of Recombinant DNA Technology and Reverse Genetics

Genomics: Genetics From a Whole-Genome Perspective

Cytoplasmic Inheritance and the Evolution of Organelle Genomes

Developmental Genetics

Genetic Analysis of Quantitative Traits

Population Genetics and Evolution

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