Question 1

At which stage does chromosome organization change from diffuse/uncondensed to a compact/condensed state?

Accepted Answer

A)  interphase 
B)  prophase 
C)  telophase 
D)  metaphase 
E)  anaphase 
A)  interphase 
B)  prophase 
C)  telophase 
D)  metaphase 
E)  anaphase

Question 2

If a cell has accumulated DNA damage, it is unlikely to

Accepted Answer

A)  pass the G2 checkpoint. 
B)  synthesize cyclin- dependent kinases. 
C)  activate DNA repair mechanisms. 
D)  enter G1 from mitosis. 
A)  pass the G2 checkpoint. 
B)  synthesize cyclin- dependent kinases. 
C)  activate DNA repair mechanisms. 
D)  enter G1 from mitosis.

Question 3

A parent cell divides to form two genetically identical daughter cells in the process of mitosis. For mitosis to take place

Accepted Answer

A)  the parent cell must reproduce its DNA during telophase. 
B)  the parent cell must replicate its entire genome prior to mitosis. 
C)  the parent cell must first be fertilized. 
D)  the parent cell must divide its DNA in half so each daughter cell gets only the genes needed to carry out its functions. In this way, differentiation occurs. 
A)  the parent cell must reproduce its DNA during telophase. 
B)  the parent cell must replicate its entire genome prior to mitosis. 
C)  the parent cell must first be fertilized. 
D)  the parent cell must divide its DNA in half so each daughter cell gets only the genes needed to carry out its functions. In this way, differentiation occurs.

Question 4

In human and many other eukaryotic species' cells, the nuclear membrane has to disappear in order for what to take place?

Accepted Answer

A)  cytokinesis 
B)  attachment of mitotic spindle to kinetochores 
C)  disassembly of the nucleolus 
D)  splitting of the centrosomes 
A)  cytokinesis 
B)  attachment of mitotic spindle to kinetochores 
C)  disassembly of the nucleolus 
D)  splitting of the centrosomes

Question 5

The microtubular organizing center found in animal cells is an identifiable structure present during all phases of the cell cycle. Specifically, it is known as which of the following?

Accepted Answer

A)  kinetochore 
B)  cell plate 
C)  centrosome 
D)  centromere 
A)  kinetochore 
B)  cell plate 
C)  centrosome 
D)  centromere

Question 6

What happens when MPF mitosis- promoting factor) is introduced into immature frog oocytes that are arrested in G2?

Accepted Answer

A)  Cell differentiation is triggered. 
B)  The cells enter mitosis. 
C)  Fertilization occurs. 
D)  Nothing happens. 
A)  Cell differentiation is triggered. 
B)  The cells enter mitosis. 
C)  Fertilization occurs. 
D)  Nothing happens.

Question 7

DNA is composed of four nucleosides: adenosine, cytidine, thymidine, and guanosine. If scientists introduced radioactive thymidine into the growth medium of the cells, it would be incorporated into the DNA molecule

Accepted Answer

A)  at any point in the cell cycle. 
B)  during DNA replication. 
C)  as the cell enters G1 of interphase. 
D)  when centromeres split so the two chromosomes can be separated. 
A)  at any point in the cell cycle. 
B)  during DNA replication. 
C)  as the cell enters G1 of interphase. 
D)  when centromeres split so the two chromosomes can be separated.

Question 8

Which cytoskeletal proteins are important constituents of the contractile structures that form the cleavage furrows involved in animal cell cytokinesis?

Accepted Answer

A)  elastin 
B)  dynein 
C)  actin 
D)  tubulin 
A)  elastin 
B)  dynein 
C)  actin 
D)  tubulin

Question 9

FtsZ is a bacterial cytoskeletal protein. It forms a contractile ring involved in bacterial cytokinesis. Its function is analogous to

Accepted Answer

A)  the cleavage furrow of eukaryotic animal cells. 
B)  the cell plate of eukaryotic plant cells. 
C)  the microtubular organizing center of eukaryotic cells. 
D)  the mitotic spindle of eukaryotic cells. 
A)  the cleavage furrow of eukaryotic animal cells. 
B)  the cell plate of eukaryotic plant cells. 
C)  the microtubular organizing center of eukaryotic cells. 
D)  the mitotic spindle of eukaryotic cells.

Question 10

Nerve cells lose their ability to undergo mitosis. Instead, they are permanently stuck in

Accepted Answer

A)  S of interphase. 
B)  G2. 
C)  G0. 
D)  meiosis. 
A)  S of interphase. 
B)  G2. 
C)  G0. 
D)  meiosis.

Question 11

In the process of chromosome separation, how do microtubules maintain contact with the kinetochores and shorten at the same time?

Accepted Answer

A)  Motor proteins move chromosomes down the microtubular structures of the mitotic spindle. 
B)  The centrosomes move apart, so the microtubular proteins do not need to shorten. 
C)  Actin microfilaments cause the microtubular proteins to slide past each other. 
D)  The centrosomes cause the shortening and depolymerization of the microtubular proteins. 
A)  Motor proteins move chromosomes down the microtubular structures of the mitotic spindle. 
B)  The centrosomes move apart, so the microtubular proteins do not need to shorten. 
C)  Actin microfilaments cause the microtubular proteins to slide past each other. 
D)  The centrosomes cause the shortening and depolymerization of the microtubular proteins.

Question 12

The drug cytochalasin B blocks the function of actin. Which of the following aspects of the cell cycle would be most disrupted by cytochalasin B?

Accepted Answer

A)  spindle attachment to kinetochores 
B)  cleavage furrow formation and cytokinesis 
C)  cell elongation during anaphase 
D)  spindle formation 
E)  DNA synthesis 
A)  spindle attachment to kinetochores 
B)  cleavage furrow formation and cytokinesis 
C)  cell elongation during anaphase 
D)  spindle formation 
E)  DNA synthesis

Question 13

Researchers pulsed rapidly dividing cultured cells for 30 minutes with radioactive thymidine. The cells were then exposed to a solution containing non- radiolabeled thymidine. Cells were analyzed at 2- hour intervals. At the 2- hour time point, no cells appeared to be dividing. Only after 4 hours did some labeled cells appear to be in M phase. This result can be explained in the following way:

Accepted Answer

A)  The cells were arrested in a nondividing state because of the treatment and could not enter M phase until several hours after the label was removed. 
B)  There seems to be a gap or a lag in the cell cycle, between the synthesis of DNA and cell division. 
C)  Synthesis S) phase is lengthy-about 12 hours in most cell types-and the radioactive thymidine was not present long enough for most cells to be labeled. 
D)  Cultured cells all divide at the same time, and none synthesized DNA during the 30- minute labeling period. 
A)  The cells were arrested in a nondividing state because of the treatment and could not enter M phase until several hours after the label was removed. 
B)  There seems to be a gap or a lag in the cell cycle, between the synthesis of DNA and cell division. 
C)  Synthesis S) phase is lengthy-about 12 hours in most cell types-and the radioactive thymidine was not present long enough for most cells to be labeled. 
D)  Cultured cells all divide at the same time, and none synthesized DNA during the 30- minute labeling period.

Question 14

Following the attachment of spindle microtubules to kinetochores, chromosomes are moved around by

Accepted Answer

A)  motor activity taking place in the centrosomes. 
B)  elongation and shortening of microtubules. 
C)  histones. 
D)  myosin motor proteins. 
A)  motor activity taking place in the centrosomes. 
B)  elongation and shortening of microtubules. 
C)  histones. 
D)  myosin motor proteins.

Question 15

At the end of mitosis, each G1 daughter cell has

Accepted Answer

A)  identical DNA to that of the G1 parent cell. 
B)  twice the cytoplasm and the same amount of DNA as the G1 parent cell. 
C)  twice the DNA and half the cytoplasm of the G1 parent cell. 
D)  half the DNA and half the cytoplasm of the G1 parent cell. 
A)  identical DNA to that of the G1 parent cell. 
B)  twice the cytoplasm and the same amount of DNA as the G1 parent cell. 
C)  twice the DNA and half the cytoplasm of the G1 parent cell. 
D)  half the DNA and half the cytoplasm of the G1 parent cell.

Question 16

Figure 12.1
-Based on structures present in the figure above, this cell is in which substage of interphase?

Accepted Answer

A)  G0 phase 
B)  G2 phase 
C)  S phase 
D)  G1 phase 
A)  G0 phase 
B)  G2 phase 
C)  S phase 
D)  G1 phase

Question 17

Masses of noninvasive cells that remain at their site of origin are known as _ tumours.

Accepted Answer

A)  benign 
B)  malignant 
C)  secondary 
D)  metastatic 
A)  benign 
B)  malignant 
C)  secondary 
D)  metastatic

Question 18

Regulatory proteins that serve to prevent a cell from entering the S phase under conditions of DNA damage are also known as

Accepted Answer

A)  antibodies. 
B)  tumour suppressors. 
C)  cyclin- dependent kinases. 
D)  cyclins. 
A)  antibodies. 
B)  tumour suppressors. 
C)  cyclin- dependent kinases. 
D)  cyclins.

Question 19

In the figure provided, G1 is represented by which numbered parts) of the cycle?

Accepted Answer

A)  V only 
B)  III only 
C)  IV only 
D)  I or V 
E)  II or IV 
A)  V only 
B)  III only 
C)  IV only 
D)  I or V 
E)  II or IV

Exam 12: The Cell Cycle

At which stage does chromosome organization change from diffuse/uncondensed to a compact/condensed state?

If a cell has accumulated DNA damage, it is unlikely to

A parent cell divides to form two genetically identical daughter cells in the process of mitosis. For mitosis to take place

In human and many other eukaryotic species' cells, the nuclear membrane has to disappear in order for what to take place?

The microtubular organizing center found in animal cells is an identifiable structure present during all phases of the cell cycle. Specifically, it is known as which of the following?

What happens when MPF mitosis- promoting factor) is introduced into immature frog oocytes that are arrested in G2?

DNA is composed of four nucleosides: adenosine, cytidine, thymidine, and guanosine. If scientists introduced radioactive thymidine into the growth medium of the cells, it would be incorporated into the DNA molecule

Which cytoskeletal proteins are important constituents of the contractile structures that form the cleavage furrows involved in animal cell cytokinesis?

FtsZ is a bacterial cytoskeletal protein. It forms a contractile ring involved in bacterial cytokinesis. Its function is analogous to

Nerve cells lose their ability to undergo mitosis. Instead, they are permanently stuck in

In the process of chromosome separation, how do microtubules maintain contact with the kinetochores and shorten at the same time?

The drug cytochalasin B blocks the function of actin. Which of the following aspects of the cell cycle would be most disrupted by cytochalasin B?

Following the attachment of spindle microtubules to kinetochores, chromosomes are moved around by

At the end of mitosis, each G1 daughter cell has

Figure 12.1 -Based on structures present in the figure above, this cell is in which substage of interphase?

Masses of noninvasive cells that remain at their site of origin are known as _ tumours.

Regulatory proteins that serve to prevent a cell from entering the S phase under conditions of DNA damage are also known as

In the figure provided, G1 is represented by which numbered parts) of the cycle?

Biology and the Tree of Life

Water and Carbon: the Chemical Basis of Life

Protein Structure and Function

Nucleic Acids and the Rna World

An Introduction to Carbohydrates

Lipids, Membranes, and the First Cells

Inside the Cell

Energy and Enzymes

Cellular Respiration and Fermentation

Photosynthesis

Cellcell Interactions

Meiosis

Mendel and the Gene

Dna and the Gene: Synthesis and Repair

How Genes Work

Transcription, Rna Processing, and Translation

Control of Gene Expression in Bacteria

Control of Gene Expression in Eukaryotes

The Molecular Revolution: Biotechnology and Beyond

Gene Structure and Development

Evolution by Natural Selection

Evolutionary Processes

Speciation

Phylogenies and the History of Life

Bacteria and Archaea

Protists

Green Algae and Land Plants

Fungi

An Introduction to Animals

Protostome Animals

Deuterostome Animals

Viruses

Plant Form and Function

Water and Sugar Transport in Plants

Plant Nutrition

Plant Sensory Systems, Signals, and Responses

Plant Reproduction and Development

Animal Form and Function

Water and Electrolyte Balance in Animals

Animal Nutrition

Gas Exchange and Circulation

Animal Nervous Systems

Animal Sensory Systems

Animal Movement

Chemical Signals in Animals

Animal Reproduction and Development

The Immune System in Animals

An Introduction to Ecology

Behavioural Ecology

Population Ecology

Community Ecology

Ecosystems and Global Ecology

Biodiversity and Conservation Biology

Filters

What happens when MPF mitosis- promoting factor) is introduced into immature frog oocytes that are arrested in G₂?

At the end of mitosis, each G₁daughter cell has

In the figure provided, G₁is represented by which numbered parts) of the cycle?