Question 1

Describe how microtubules and cohesion work together to align the chromosomes along the metaphase plate during the process of sister chromatid cohesion.

Accepted Answer

Kinetochore microtubules are attached to the kinetochore at each centromere of sister chromatids.Because they are tethered to kinetochore microtubules from opposite centrosomes,the sister chromatids experience opposing forces that are critical to the positioning of chromosomes along an imaginary midline at the equator of the cell.This imaginary line is called the metaphase plate.The tension created by the pull of kinetochore microtubules is balanced by a companion process known as sister chromatid cohesion.Sister chromatid cohesion is produced by the protein cohesin that localizes between the sister chromatids and holds them together to resist the pull of kinetochore microtubules.As microtubules move chromosomes toward the midline of the cell,cohesin helps keep the sister chromatids together to ensure proper chromosome positioning and to prevent their premature separation.

Question 2

Females have two copies of the X chromosome,so they can be homozygous or heterozygous for any genes found on the X chromosome.Males have only one copy of the X chromosome;what term is used to describe this inheritance state?

Accepted Answer

hemizygous

Question 3

How do protein kinases generally activate their target proteins?

Accepted Answer

A) The process of phosphorylation causes the target to change conformation. 
B) The kinases bind to target proteins directly,forming a complex that activates the protein and lets them change conformations. 
C) Kinases vary their concentrations through the cell cycle,so that proteins are activated only when kinase levels are high. 
D) Kinases bind to target proteins and inactivate them,so kinase levels must drop for target protein activation. 
E) The process of dephosphorylation causes the target to change conformations. 
A) The process of phosphorylation causes the target to change conformation. 
B) The kinases bind to target proteins directly,forming a complex that activates the protein and lets them change conformations. 
C) Kinases vary their concentrations through the cell cycle,so that proteins are activated only when kinase levels are high. 
D) Kinases bind to target proteins and inactivate them,so kinase levels must drop for target protein activation. 
E) The process of dephosphorylation causes the target to change conformations. A

Question 4

The separation of sister chromatids during anaphase I of mitosis is known as chromosome

Accepted Answer

A) cytokinesis. 
B) karyokinesis. 
C) crossing over. 
D) synapsis. 
E) disjunction. 
A) cytokinesis. 
B) karyokinesis. 
C) crossing over. 
D) synapsis. 
E) disjunction.

Question 5

Any mechanism that compensates for differences in the number of copies of genes due to the different chromosome constitutions of males and females is called what?

Accepted Answer

The answer of Any mechanism that compensates for differences in...

Question 6

In meiosis I,the diploid number (2n)of chromosomes is reduced to the haploid number (n)because of the separation of what?

Accepted Answer

homologous

Question 7

How do cyclin-dependent kinases help regulate the cell cycle?

Accepted Answer

As cells move through the cell cycle,rea

Question 8

When cyclin D1 is expressed in normal levels,it stimulates the cell cycle.If overexpressed,it can promote cancer by allowing cells to overproliferate.A normal gene with the potential to cause cancer if mutated and/or overexpressed is known as what?

Accepted Answer

The answer of When cyclin D1 is expressed in normal...

Question 9

What is the short segment of the cell cycle during which cells divide?

Accepted Answer

The answer of What is the short segment of the...

Question 10

What are the three important differences between mitosis and meiosis I?

Accepted Answer

In meiosis I,but not in mitosis,the foll

Question 11

At the end of the G₁ stage,cells have the option of entering which two phases?

Accepted Answer

The answer of At the end of the G₁ stage,cells...

Question 12

How many homologous pairs of chromosomes are found in a human somatic cell nucleus?

Accepted Answer

The answer of How many homologous pairs of chromosomes are...

Question 13

Mutations that inhibit Rb gene expression will have what effect on cell proliferation?

Accepted Answer

A) Cells will proliferate less,even if excess growth factors are present. 
B) Cells will proliferate less because growth factors are absent. 
C) Cells will proliferate more because growth factors are produced in excess. 
D) Cells will proliferate more,regardless of growth factor concentration. 
E) There will be no effect on cell proliferation;only apoptosis occurs. 
A) Cells will proliferate less,even if excess growth factors are present. 
B) Cells will proliferate less because growth factors are absent. 
C) Cells will proliferate more because growth factors are produced in excess. 
D) Cells will proliferate more,regardless of growth factor concentration. 
E) There will be no effect on cell proliferation;only apoptosis occurs.

Question 14

This protein assures that sister chromatids of each chromosome remain firmly joined and can resist the pull of the kinetochore microtubules.

Accepted Answer

The answer of This protein assures that sister chromatids of...

Question 15

Mitosis is a process of cell division that results in

Accepted Answer

A) two unique daughter cells. 
B) four unique daughter cells. 
C) two identical daughter cells. 
D) three identical daughter cells. 
E) four identical daughter cells. 
A) two unique daughter cells. 
B) four unique daughter cells. 
C) two identical daughter cells. 
D) three identical daughter cells. 
E) four identical daughter cells.

Question 16

Tumor suppressors are genes that

Accepted Answer

A) promote advancement of the cell cycle. 
B) phosphorylate proteins involved in the cell cycle. 
C) block progression of the cell cycle. 
D) prevent apoptosis in normal cells. 
E) activate proto-oncogenes. 
A) promote advancement of the cell cycle. 
B) phosphorylate proteins involved in the cell cycle. 
C) block progression of the cell cycle. 
D) prevent apoptosis in normal cells. 
E) activate proto-oncogenes.

Question 17

The binding of nonsister chromatids by a synaptonemal complex draws the homologs into close contact so that what process can occur?

Accepted Answer

A) cytokinesis 
B) karyokinesis 
C) independent assortment 
D) synapsis 
E) disjunction 
A) cytokinesis 
B) karyokinesis 
C) independent assortment 
D) synapsis 
E) disjunction

Question 18

How many sister chromatids are found in a human somatic cell nucleus during mitosis?

Accepted Answer

The answer of How many sister chromatids are found in...

Question 19

Morgan's analysis of a white-eyed male Drosophila mutation helped explain

Accepted Answer

A) autosomal dominance. 
B) random mutation. 
C) crossing over. 
D) independent assortment. 
E) X-linked inheritance. 
A) autosomal dominance. 
B) random mutation. 
C) crossing over. 
D) independent assortment. 
E) X-linked inheritance.

Question 20

Single-celled eukaryotes can survive and reproduce in both haploid and diploid forms.Yeast spend most of their life cycle and actively reproduce in which form?

Accepted Answer

The answer of Single-celled eukaryotes can survive and reproduce in...

Exam 3: Cell Division and Chromosome Heredity

Describe how microtubules and cohesion work together to align the chromosomes along the metaphase plate during the process of sister chromatid cohesion.

Females have two copies of the X chromosome,so they can be homozygous or heterozygous for any genes found on the X chromosome.Males have only one copy of the X chromosome;what term is used to describe this inheritance state?

How do protein kinases generally activate their target proteins?

The separation of sister chromatids during anaphase I of mitosis is known as chromosome

Any mechanism that compensates for differences in the number of copies of genes due to the different chromosome constitutions of males and females is called what?

In meiosis I,the diploid number (2n)of chromosomes is reduced to the haploid number (n)because of the separation of what?

How do cyclin-dependent kinases help regulate the cell cycle?

When cyclin D1 is expressed in normal levels,it stimulates the cell cycle.If overexpressed,it can promote cancer by allowing cells to overproliferate.A normal gene with the potential to cause cancer if mutated and/or overexpressed is known as what?

What is the short segment of the cell cycle during which cells divide?

What are the three important differences between mitosis and meiosis I?

At the end of the G₁ stage,cells have the option of entering which two phases?

How many homologous pairs of chromosomes are found in a human somatic cell nucleus?

Mutations that inhibit Rb gene expression will have what effect on cell proliferation?

This protein assures that sister chromatids of each chromosome remain firmly joined and can resist the pull of the kinetochore microtubules.

Mitosis is a process of cell division that results in

Tumor suppressors are genes that

The binding of nonsister chromatids by a synaptonemal complex draws the homologs into close contact so that what process can occur?

How many sister chromatids are found in a human somatic cell nucleus during mitosis?

Morgan's analysis of a white-eyed male Drosophila mutation helped explain

Single-celled eukaryotes can survive and reproduce in both haploid and diploid forms.Yeast spend most of their life cycle and actively reproduce in which form?

The Molecular Basis of Heredity, Variation, and Evolution

Transmission Genetics

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

Chromosome Structure

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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