Chapter 12; Cell Cycle – Flashcards

question
All of the following statements are true except:
answer
The motic spindles in prokaryotic cells are composed of microtubules
question
The centromere is a region in which
answer
Chromatids are attached to one another
question
Two centromeres are arranged at opposite poles of the cell
answer
Prometaphase
question
Centrioles begin to move apart in animal cells.
answer
Prophase
question
This is longest of the mitotic stages.
answer
Phophase
question
Centromeres uncouple, sister chromatids are seperated, and the two new chromosomes move to opposite poles of the cell
answer
Anaphase
question
If cells in the process of dividing are subjected to colchicine, a drug that interferes with the functioning of the spindle apparatus, at which stage will mitosis be arrested?
answer
Metaphase
question
A cell containing 92 chromatids at metaphase of mitosis would, at its completion, produce two nuclei containing how many chromosomes?
answer
46
question
All of the following occur during prometaphase of mitosis in animal cells except
answer
Chromosomes are duplicated
question
If there are 20 centromeress in a cell, how many chromosomes are there?
answer
20
question
Of the following, the best conclusion concerning the difference between the S phase for beta and grama is that
answer
gamma contains more DNA than beta
question
The best conclusion concering delta is that the cells
answer
Containonly one chromosomethat is very short
question
The S phase was measured by
answer
determining the start and stop of increased DNA in the cells
question
Where do the microtubules of the spindle orginate during mitosis in both plant and animal cells?
answer
Centrosome
question
All of the following occur during mitosis except
answer
The synthesis of DNA
question
if a cell has 8 chromosomes at metaphase of mitosis, how many chromosomes will it have during anaphase?
answer
16
question
Cytokinesis usually, but not always, follows mitosis. If a cell composed mitosis but not cytokinesis, what would be the result?
answer
a cell with 2 nuclei
question
reguarding mitosis and cytokinesis, one difference between higher plants and animals is that in plants
answer
a cell plate begins to form at telophase, whereas in animals a clevage furrow is initiated at that stage
question
How do the daughter cells at the end of mitosis and cytokinesis compare with their parent cell when it was in G1 of the cell cycle?
answer
the daughter cells have the same number of chromosomes and the same amount of DNA
question
The formation of a cell plate is beginning across the middle of a cell and nuclei are re-forming at opposite ends of the cell. What kind of cell is that?
answer
a plant cell unergoing cytokinesis
question
Taxol is an anticancer drug extracted from the pacific yew tree. In animal cells, taxol disrupts mictrotubles and acclerating their assembly from the protein precursor, tubulin. Suprisingly this stops mitosis. Specifically taxol must affect
answer
The fibers of the mitotic spindle
question
Which of the following is primarily responsible for cytokinesis in plant cells?
answer
Golgi- derived vesicles
question
Which of the following organisms does not reproduce cells by mitosis and cytokinesis?
answer
bacterium
question
During which phase of mitosis do we find chromosomes composed of 2 chromatids?
answer
from G2 of interphase through metaphase
question
Which of the following is not true of bacterial chromosome?
answer
Its centromeres uncouple during replication
question
I which group of eukaryotic organisms does the nuclear envelope remain intact during mitosis?
answer
dinoflagellates and diatoms
question
Movement of the chromosomes during anaphase would be most affected by a drug that
answer
Prevented shortening of microtubles
question
If mammalian cells recieve a go-ahead signal at the G1 checkpoint, they will
answer
complete the cycle and divide
question
Cells that are in a nonividing state are in which phase?
answer
G0
question
Measurements of the amount of DNA per nucleus were taken on a large number of cells from a growing fungus. The measured DNA levels ranged from 3 to 6 picograms per nucleus. In which stage of the cell cycle was the nucleus with 6 picograms of DNA?
answer
G2
question
What causes the rhythmic change in cyclin concentration in the cell cycle?
answer
Its destruction by an enzyme phosphorylated by MPF
question
released by platelets in the vicinity of an injury
answer
PDGF
question
enzymes that activate or inactivate other proteins by phosphorylating them
answer
Protain kinase
question
fibroblasts have receptors fro this substance on their plasma membranes
answer
PDGF
question
a protein synthesized through the cell cycle that associates with a kiase to form active enzymes
answer
cyclin
question
triggers the cell's passage past the G2 checkpoint into mitosis
answer
MPF
question
the "restriction point" occurs here
answer
G1
question
nerve and muscle cells are in this phase
answer
G0
question
the shortest part of cell cycle
answer
M
question
DNA is replicated at this time of the cell cycle
answer
Protein Kinase
question
Cyclin is destroyed toward the end of this phase
answer
M
question
What are enzymes called that control the activites of other proteins by phosphorylating them?
answer
kinase
question
a group of cells is assayed for DNA content immediately following mitosis and is found to have an average of 8 picograms of DNA per nucleus. THose cells woul have ____ picograms at the end of the S phase and ________ picograms at the end of G2
answer
16 ... 16
question
As the cell progresses through prophase and into metaphase, ehat happens to the active anaphase-promoting complex proteins?
answer
they increase sharply once all the chromosomes are lined up in metaphase
question
what triggers the seperation of chromatids during mitosis?
answer
activation of an anaphase-promoting complex
question
Proteins that are involved in the regulation of the cell cycle, and that show fluctuations in concentration during the cell cycle, are called
answer
cyclins
question
THe MPF protein complex turns itself off by
answer
activating an enzyme that destroys cyclin
question
recent research has indicated that cancer cells
answer
transform normal cells by altering genes involved in the control of mitosis
question
a mutation results in a cell that no longer produces a normal protein kinase for the M phase checkpoint. Which of the following would likely be the immediate result of this mutation?
answer
the cell would undergo normal mitosis, but fail to enter the next G1
question
Density-dependent inhibition is explained by which of the following?
answer
as the cells become more numerous, the amount of required growth factors and nutrients per cell becomes insufficient to allow for cell growth
question
Which of the following is true concering cancer cells?
answer
they do not exhibit density-dependent inhibition when growing in culture,when they stop dividing they do so at random points in the cell cycle, and they have escaped from cell cycle controls
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question
All of the following statements are true except:
answer
The motic spindles in prokaryotic cells are composed of microtubules
question
The centromere is a region in which
answer
Chromatids are attached to one another
question
Two centromeres are arranged at opposite poles of the cell
answer
Prometaphase
question
Centrioles begin to move apart in animal cells.
answer
Prophase
question
This is longest of the mitotic stages.
answer
Phophase
question
Centromeres uncouple, sister chromatids are seperated, and the two new chromosomes move to opposite poles of the cell
answer
Anaphase
question
If cells in the process of dividing are subjected to colchicine, a drug that interferes with the functioning of the spindle apparatus, at which stage will mitosis be arrested?
answer
Metaphase
question
A cell containing 92 chromatids at metaphase of mitosis would, at its completion, produce two nuclei containing how many chromosomes?
answer
46
question
All of the following occur during prometaphase of mitosis in animal cells except
answer
Chromosomes are duplicated
question
If there are 20 centromeress in a cell, how many chromosomes are there?
answer
20
question
Of the following, the best conclusion concerning the difference between the S phase for beta and grama is that
answer
gamma contains more DNA than beta
question
The best conclusion concering delta is that the cells
answer
Containonly one chromosomethat is very short
question
The S phase was measured by
answer
determining the start and stop of increased DNA in the cells
question
Where do the microtubules of the spindle orginate during mitosis in both plant and animal cells?
answer
Centrosome
question
All of the following occur during mitosis except
answer
The synthesis of DNA
question
if a cell has 8 chromosomes at metaphase of mitosis, how many chromosomes will it have during anaphase?
answer
16
question
Cytokinesis usually, but not always, follows mitosis. If a cell composed mitosis but not cytokinesis, what would be the result?
answer
a cell with 2 nuclei
question
reguarding mitosis and cytokinesis, one difference between higher plants and animals is that in plants
answer
a cell plate begins to form at telophase, whereas in animals a clevage furrow is initiated at that stage
question
How do the daughter cells at the end of mitosis and cytokinesis compare with their parent cell when it was in G1 of the cell cycle?
answer
the daughter cells have the same number of chromosomes and the same amount of DNA
question
The formation of a cell plate is beginning across the middle of a cell and nuclei are re-forming at opposite ends of the cell. What kind of cell is that?
answer
a plant cell unergoing cytokinesis
question
Taxol is an anticancer drug extracted from the pacific yew tree. In animal cells, taxol disrupts mictrotubles and acclerating their assembly from the protein precursor, tubulin. Suprisingly this stops mitosis. Specifically taxol must affect
answer
The fibers of the mitotic spindle
question
Which of the following is primarily responsible for cytokinesis in plant cells?
answer
Golgi- derived vesicles
question
Which of the following organisms does not reproduce cells by mitosis and cytokinesis?
answer
bacterium
question
During which phase of mitosis do we find chromosomes composed of 2 chromatids?
answer
from G2 of interphase through metaphase
question
Which of the following is not true of bacterial chromosome?
answer
Its centromeres uncouple during replication
question
I which group of eukaryotic organisms does the nuclear envelope remain intact during mitosis?
answer
dinoflagellates and diatoms
question
Movement of the chromosomes during anaphase would be most affected by a drug that
answer
Prevented shortening of microtubles
question
If mammalian cells recieve a go-ahead signal at the G1 checkpoint, they will
answer
complete the cycle and divide
question
Cells that are in a nonividing state are in which phase?
answer
G0
question
Measurements of the amount of DNA per nucleus were taken on a large number of cells from a growing fungus. The measured DNA levels ranged from 3 to 6 picograms per nucleus. In which stage of the cell cycle was the nucleus with 6 picograms of DNA?
answer
G2
question
What causes the rhythmic change in cyclin concentration in the cell cycle?
answer
Its destruction by an enzyme phosphorylated by MPF
question
released by platelets in the vicinity of an injury
answer
PDGF
question
enzymes that activate or inactivate other proteins by phosphorylating them
answer
Protain kinase
question
fibroblasts have receptors fro this substance on their plasma membranes
answer
PDGF
question
a protein synthesized through the cell cycle that associates with a kiase to form active enzymes
answer
cyclin
question
triggers the cell's passage past the G2 checkpoint into mitosis
answer
MPF
question
the "restriction point" occurs here
answer
G1
question
nerve and muscle cells are in this phase
answer
G0
question
the shortest part of cell cycle
answer
M
question
DNA is replicated at this time of the cell cycle
answer
Protein Kinase
question
Cyclin is destroyed toward the end of this phase
answer
M
question
What are enzymes called that control the activites of other proteins by phosphorylating them?
answer
kinase
question
a group of cells is assayed for DNA content immediately following mitosis and is found to have an average of 8 picograms of DNA per nucleus. THose cells woul have ____ picograms at the end of the S phase and ________ picograms at the end of G2
answer
16 ... 16
question
As the cell progresses through prophase and into metaphase, ehat happens to the active anaphase-promoting complex proteins?
answer
they increase sharply once all the chromosomes are lined up in metaphase
question
what triggers the seperation of chromatids during mitosis?
answer
activation of an anaphase-promoting complex
question
Proteins that are involved in the regulation of the cell cycle, and that show fluctuations in concentration during the cell cycle, are called
answer
cyclins
question
THe MPF protein complex turns itself off by
answer
activating an enzyme that destroys cyclin
question
recent research has indicated that cancer cells
answer
transform normal cells by altering genes involved in the control of mitosis
question
a mutation results in a cell that no longer produces a normal protein kinase for the M phase checkpoint. Which of the following would likely be the immediate result of this mutation?
answer
the cell would undergo normal mitosis, but fail to enter the next G1
question
Density-dependent inhibition is explained by which of the following?
answer
as the cells become more numerous, the amount of required growth factors and nutrients per cell becomes insufficient to allow for cell growth
question
Which of the following is true concering cancer cells?
answer
they do not exhibit density-dependent inhibition when growing in culture,when they stop dividing they do so at random points in the cell cycle, and they have escaped from cell cycle controls