Chapter 11 Launchpad
What is the function of histone proteins? - to organize the microtubules that make up the spindle - to connect chromosomes to the mitotic spindle - to package DNA in eukaryotic chromosomes - to attach sister chromatids together
to package DNA in eukaryotic chromosomes
The process of cell division in a prokaryotic cell is called: - binary fission. - mitosis. - binary fusion. - cytokinesis.
binary fission
Which of the answer choices is a characteristic of meiotic cell division? - Meiotic cell division results in halving the number of chromosomes. - The cells produced by meiosis are genetically identical. - Meiotic cell division ultimately results in the formation of two cells. - Meiotic cell division requires two rounds of DNA replication.
Meiotic cell division results in halving the number of chromosomes.
It is estimated that a human cell in G1 phase of the cell cycle contains 6 picograms of DNA in its nucleus. If you measure the DNA content at various stages of mitosis and meiosis, what amounts of DNA can be expected in nuclei at the following stages? prophase mitosis: _____; prophase I meiosis: _____; prophase II meiosis: _____; telophase mitosis: _____; telophase meiosis II: _____. (All amounts are in picograms (10-12 g.) - 12; 12; 6; 6; 3 - 12; 24; 6; 12; 6 - 12; 12; 3; 6; 3 - 6; 12; 3; 6; 3 - 6; 6; 3; 6; 3
12; 12; 6; 6; 3
How many chromosome pairs are there in a normal human genome? - 23 - 22 - 46 - 64
23
At the start of mitosis, how many sister chromatids are present in a human cell? - 46 - 23 - 12 - 92
46
In human cells, at the end of mitosis and after cytokinesis, how many chromatids have moved into each daughter cell? - 46 - 23 - 92 - 22
46
Which of the answer choices is true about gametes? - They fuse to form a new organism during fertilization. - They have the same number of chromosomes as a somatic cell of the same individual. - They are formed by mitotic cell division. - They are genetically identical to other gametes formed during meiosis. - They are found in animals but not plants.
They fuse to form a new organism during fertilization.
To visualize chromosomes, a picture of each can be arranged such that homologous chromosomes are aligned with each other and arranged as pairs in order of decreasing size. What is this called? - a genotype - a prototype - a phenotype - a karyotype
a karyotype
To visualize chromosomes, a picture of each can be arranged such that homologous chromosomes are aligned with each other and arranged as pairs in order of decreasing size. What is this called? - a karyotype - a prototype - a genotype - a phenotype
a karyotype
What protein forms the contractile ring during cytokinesis in animal cells? - DNA polymerase - dynein - kinesin - actin
actin
What protein forms the contractile ring during cytokinesis in animal cells? - kinesin - DNA polymerase - actin - dynein
actin
What cellular process(es) is/are responsible for the increase in protein content associated with the gap phases of the cell cycle? - translation alone - transcription alone - glycolysis - both transcription and translation
both transcription and translation
The division of the cell's cytoplasm in a eukaryotic cell is known as: - cytokinesis. - cell fission. - mitosis. - both cytokinesis and mitosis.
cytokinesis.
During meiosis I: - genetically identical daughter cells are formed. - gametes are formed. - diploid cells become haploid. - sister chromatids are separated.
diploid cells become haploid.
A phragmoplast functions to: - stimulate the growth of the microtubule spindle. - break down the nuclear envelope. - anchor microtubules to sister chromatids. - form a new cell wall.
form a new cell wall
Which of the answer choices is part of the process of binary fission in prokaryotes? - condensation of chromosomes - rearrangement of the microtubule cytoskeleton - separation of sister chromatids - formation of a new cell wall
formation of a new cell wall
Why don't plant cells use a contractile ring to divide their daughter cells? - Plant cells don't form daughter cells. - A contractile ring can't "pinch" a cell wall. - Plant cells don't have an actin cytoskeleton. - Plant cells don't have plasma membranes.
A contractile ring can't "pinch" a cell wall.
Muscle cells in the mammalian heart are multinucleate, meaning that multiple nuclei are present in the cytoplasm of individual large cells. Predict what is different about the cell cycle in a muscle cell. - Cytokinesis does not occur. - The G1 and G2 phases are extended. - S phase happens twice. - M phase is inhibited.
Cytokinesis does not occur.
Muscle cells in the mammalian heart are multinucleate, meaning that multiple nuclei are present in the cytoplasm of individual large cells. Predict what is different about the cell cycle in a muscle cell. - S phase happens twice. - M phase is inhibited. - The G1 and G2 phases are extended. - Cytokinesis does not occur.
Cytokinesis does not occur.
Meiosis _____ is similar to mitosis in that _____ separate. - I; sister chromatids - II; sister chromatids - II; homologous chromosomes - I; homologous chromosomes - I; non-sister chromatids
II; sister chromatids
What characteristics do you expect to observe with a microscope if you investigate the division of mitochondria and chloroplasts in eukaryotic cells? - circular DNA attached to the plasma membrane and binary fission - non-circular DNA and division by mitosis - circular DNA attached to the plasma membrane and division by mitosis - mitochondria and chloroplasts replicating by a process unlike binary fission or mitosis
circular DNA attached to the plasma membrane and binary fission
Would genetic recombination result if crossing over occurred between sister chromatids? - No, because sister chromatids are genetically identical or nearly identical. - No, because many genes are present along the entire length of a chromosome. - Yes, because any rearrangement of DNA produces new combinations of alleles. - Yes, because genetic diversity would decrease due to the loss of gene combinations.
No, because sister chromatids are genetically identical or nearly identical.
A researcher is studying phases of the cell cycle in a population of cells during which there is an increase in the DNA content. This stage is most likely: - cytokinesis. - S phase. - G1 phase. - mitosis.
S phase.
Which statement represents a misconception about sister chromatids? - Sister chromatids are also called homologous chromosomes. - Sister chromatids are identical or nearly identical DNA sequences. - Sister chromatids are formed in the S phase of the cell cycle when the chromosome undergoes replication. - Sister chromatids are attached to each other at their centromeres. - Sister chromatids are formed when the prokaryotic circular chromosome attaches at the plasma membrane.
Sister chromatids are formed when the prokaryotic circular chromosome attaches at the plasma membrane.
What would happen to the daughter cells if the G2 phase of the parent cell is shortened? - The cells would be larger than normal. - The cells would be missing chromosomes. - The cells would not undergo cytokinesis. - The cells would be smaller than normal.
The cells would be smaller than normal.
What would happen to the daughter cells if the G2 phase of the parent cell is shortened? - The cells would not undergo cytokinesis. - The cells would be missing chromosomes. - The cells would be larger than normal. - The cells would be smaller than normal.
The cells would be smaller than normal.
What characteristics do you expect to observe with a microscope if you investigate the division of mitochondria and chloroplasts in eukaryotic cells? - circular DNA attached to the plasma membrane and division by mitosis - mitochondria and chloroplasts replicating by a process unlike binary fission or mitosis - non-circular DNA and division by mitosis - circular DNA attached to the plasma membrane and binary fission
circular DNA attached to the plasma membrane and binary fission
Suppose you analyze a time-lapse video of a cell under a microscope and you observe what appears to be crosslike structures within a bivalent. Which of the answer choices is an interpretation of this observation? - The cell has completed S phase and is ready to begin cell division. - These structures represent crossing over between non-sister chromatids. - The chromatids are the result of crossing over prior to initiation of Prophase 1 of meiosis. - The cell is probably from a plant that has four sets of chromosomes, rather than only two sets.
These structures represent crossing over between non-sister chromatids.
Suppose you analyze a time-lapse video of a cell under a microscope and you observe what appears to be crosslike structures within a bivalent. Which of the answer choices is an interpretation of this observation? - These structures represent crossing over between non-sister chromatids. - The chromatids are the result of crossing over prior to initiation of Prophase 1 of meiosis. - The cell is probably from a plant that has four sets of chromosomes, rather than only two sets. - The cell has completed S phase and is ready to begin cell division.
These structures represent crossing over between non-sister chromatids.
Why are the X and Y chromosomes not considered homologous? - They are named after two different letters of the alphabet. - The do not pair during metaphase in meiosis. - They only occur in polar bodies. - They do not carry the same set of genes.
They do not carry the same set of genes.
Why are the X and Y chromosomes not considered homologous? - They do not carry the same set of genes. - They are named after two different letters of the alphabet. - The do not pair during metaphase in meiosis. - They only occur in polar bodies.
They do not carry the same set of genes.
The prokaryotic protein FtsZ is evolutionarily related to eukaryotic tubulin. What does this mean? - All of these choices are correct. - The amino acid sequence for FtsZ is similar to tubulin. - The overall protein structure of FtsZ is similar to tubulin. - The two proteins evolved from a common ancestral protein. - The gene sequence for FtsZ is similar to tubulin.
all of these answer choices are correct
In which phase of mitosis do spindle microtubules shorten? - telophase - metaphase - anaphase - prophase
anaphase
During what step in meiosis do homologous chromosomes separate? - anaphase I - prophase II - metaphase II - anaphase II
anaphase I
When do sister chromatids separate in meiosis? - anaphase II - metaphase II - anaphase I - telophase I
anaphase II
When do sister chromatids separate in meiosis? - telophase I - anaphase I - metaphase II - anaphase II
anaphase II
What cellular process(es) is/are responsible for the increase in protein content associated with the gap phases of the cell cycle? - both transcription and translation - glycolysis - translation alone - transcription alone
both transcription and translation
What cellular process(es) is/are responsible for the increase in protein content associated with the gap phases of the cell cycle? - transcription alone - translation alone - glycolysis - both transcription and translation
both transcription and translation
Non-sister chromatids are: - separated during anaphase of mitosis. - formed by replication of a single chromosome. - copies of homologs but not fully identical chromosomes. - genetically identical.
copies of homologs but not fully identical chromosomes.
Homologous chromosomes separate from each other in: - meiosis I. - mitosis. - meiosis II. - They never separate from each other during any form of cell division.
meiosis I.
In which phase of mitosis do chromosomes line up at the middle of the cell? - telophase - anaphase - prophase - metaphase
metaphase
Reproduction by mitotic cell division: - results in two daughter cells that are genetically identical. -involves the formation of gametes. -reduces the number of chromosomes by half. -does not require the replication of chromosomes.
results in two daughter cells that are genetically identical.
In which phase of mitosis does the nuclear envelope reform? - telophase - anaphase - metaphase - prophase
telophase
In which phase of mitosis does the nuclear envelope reform? - telophase - prophase - metaphase - anaphase
telophase
What would happen to the daughter cells if the G2 phase of the parent cell is shortened? - The cells would not undergo cytokinesis. - The cells would be missing chromosomes. - The cells would be smaller than normal. - The cells would be larger than normal.
the cells would be smaller than normal
Mitotic cell division is considered asexual because: - the daughter cells formed are genetically different. - this form of cell division is most similar to binary fission. - the daughter cells get different mixes of maternal and paternal chromosomes. - the daughter cells receive DNA from one parent cell, and the daughter cells are genetically identical.
the daughter cells receive DNA from one parent cell, and the daughter cells are genetically identical.
The centrosome is: - a region of the chromosome where sister chromatids are attached to each other. - the microtubule organizing center for the mitotic spindle. - a region of the chromosome where kinetochores attach. - a region of the chromosome where microtubules attach to chromosomes during mitosis.
the microtubule organizing center for the mitotic spindle.
The centrosome is: - the microtubule organizing center for the mitotic spindle. - a region of the chromosome where sister chromatids are attached to each other. - a region of the chromosome where kinetochores attach. - a region of the chromosome where microtubules attach to chromosomes during mitosis.
the microtubule organizing center for the mitotic spindle.
Which statement is true regarding binary fission? - DNA replication of the circular bacterial chromosome during binary fission is a bidirectional process, starting at one point but progressing in opposite directions. - In binary fission, cell division is typically asymmetrical, with one daughter cell appearing much smaller than the other. - Tubulin, rather than FtsZ, is responsible for cell division during binary fission. - Proteins only anchor the original circular genome to the plasma membrane; the copy produced by DNA replication is free-floating.
DNA replication of the circular bacterial chromosome during binary fission is a bidirectional process, starting at one point but progressing in opposite directions.
Predict what would happen if crossing over between homologous chromosomes occurred as part of mitosis. - Daughter cells would be genetically identical. - Daughter cells would not be genetically identical. - There would be no effect, because sister chromatids separate in anaphase. - Daughter cells would be haploid.
Daughter cells would not be genetically identical.
Predict what would happen if crossing over between homologous chromosomes occurred as part of mitosis. - There would be no effect, because sister chromatids separate in anaphase. - Daughter cells would be genetically identical. - Daughter cells would be haploid. - Daughter cells would not be genetically identical.
Daughter cells would not be genetically identical.
Meiosis _____ is sometimes called reductional division because _____. - II; the sister chromatids are separated - I; the number of chromosomes is reduced by half - I; the sister chromatids are separated - II; the amount of DNA per chromatid is reduced by half - II; the number of chromosomes is reduced by half
I; the number of chromosomes is reduced by half
At which stage of the cell cycle could you see sister chromatids with a microscope? - M - S - G1 - G2
M
At which stage of the cell cycle could you see sister chromatids with a microscope? - M - S - G2 - G1
M
During meiosis I: - diploid cells become haploid. - sister chromatids are separated. - gametes are formed. - genetically identical daughter cells are formed.
diploid cells become haploid.
Evidence exists (especially in dinoflagellates) that mitosis evolved from binary fission. For example, in certain eukaryotic cells during mitosis, DNA is attached to the membrane of the nucleus (much like a circular chromosome of a bacterium is attached to the plasma membrane). - true - false
true
The alignment of chromosomes at metaphase of meiosis II is most similar to the alignment of chromosomes during metaphase of mitosis. - true - false
true
Sexual reproduction results in an increase in genetic diversity because: . - All of these choices are correct. - during metaphase I, the bivalents line up in a random orientation so that gametes inherit a random set of maternally and paternally derived chromosomes. - during fertilization, the gametes that fuse are random so that a large number of chromosomal combinations are possible in the new organism. - during prophase I, genes that are paternally and maternally derived recombine so that the gametes have chromosomes that are different from the parents' chromosomes.
All of these choices are correct.
The second meiotic division resembles mitosis because: - All of these choices are correct. - spindle microtubules attach from opposite directions to the centromere of each sister chromatid pair. - chromosomes decondense during telophase II. - the daughter cells have the same number of chromosomes as the parent cell. - sister chromatids are separated during anaphase II to become the chromosomes of the daughter cells.
All of these choices are correct.
What would happen if a pair of sister chromatids only connected to the mitotic spindle at one of their kinetochores? - All of these choices are correct. - The sister chromatids would not separate. - The chromosome would not line up properly at metaphase. - One of the daughter cells would have an extra copy of that chromosome.
All of these choices are correct.
If you analyze the sequences of the two copies of any of the chromosomes shown in the karyotype, there would be slight sequence differences. What could account for the small differences between a few of the homologous chromosomes? - Some of this person's DNA is mutated, possibly causing disease. - The differences are a result of the way the material was prepared. - Each homologous chromosome in a pair is from a different parent. - Chromosomes may not be completely replicated during S phase.
Each homologous chromosome in a pair is from a different parent.
If you analyze the sequences of the two copies of any of the chromosomes shown in the karyotype, there would be slight sequence differences. What could account for the small differences between a few of the homologous chromosomes? - The differences are a result of the way the material was prepared. - Chromosomes may not be completely replicated during S phase. - Each homologous chromosome in a pair is from a different parent. - Some of this person's DNA is mutated, possibly causing disease.
Each homologous chromosome in a pair is from a different parent.
If you analyze the sequences of the two copies of any of the chromosomes shown in the karyotype, there would be slight sequence differences. What could account for the small differences between a few of the homologous chromosomes? - The differences are a result of the way the material was prepared. - Each homologous chromosome in a pair is from a different parent. - Some of this person's DNA is mutated, possibly causing disease. - Chromosomes may not be completely replicated during S phase.
Each homologous chromosome in a pair is from a different parent.
A cell that is not actively dividing is in what phase of the cell cycle? - G0 - G2 - S - M - G1
G0
A cell that is not actively dividing is in what phase of the cell cycle? - G2 - M - S - G1 - G0
G0
Suppose you are observing some cells with a microscope, and you see a cell that appears to be dividing. You can see that as the cell starts to pinch in half, the DNA seems to be attached to the plasma membrane via a membrane protein. On further analysis, you find that this organism's DNA is circular - that is, it consists of a closed loop. What can you conclude about this organism and its mode of cell division? - It is a eukaryote that is dividing by binary fission. - It is a prokaryote that is dividing by binary fission. - It is a prokaryote that is dividing by mitosis. - It is a eukaryote that is dividing by mitosis.
It is a prokaryote that is dividing by binary fission.
Suppose you are observing some cells with a microscope, and you see a cell that appears to be dividing. You can see that as the cell starts to pinch in half, the DNA seems to be attached to the plasma membrane via a membrane protein. On further analysis, you find that this organism's DNA is circular - that is, it consists of a closed loop. What can you conclude about this organism and its mode of cell division? - It is a prokaryote that is dividing by binary fission. - It is a eukaryote that is dividing by binary fission. - It is a prokaryote that is dividing by mitosis. - It is a eukaryote that is dividing by mitosis.
It is a prokaryote that is dividing by binary fission.
Suppose you are observing some cells with a microscope, and you see a cell that appears to be dividing. You can see that as the cell starts to pinch in half, the DNA seems to be attached to the plasma membrane via a membrane protein. On further analysis, you find that this organism's DNA is circular - that is, it consists of a closed loop. What can you conclude about this organism and its mode of cell division? - It is a prokaryote that is dividing by mitosis. - It is a eukaryote that is dividing by mitosis. - It is a eukaryote that is dividing by binary fission. - It is a prokaryote that is dividing by binary fission.
It is a prokaryote that is dividing by binary fission.
Why would a compound that interferes with bacterial cell wall synthesis be useful for treating a bacterial infection? - It would prevent replication of DNA, and it would limit the spread of the infection. - It would limit growth of the bacterial population through cell division. - It would prevent replication of DNA. - It would prevent the cells from becoming larger.
It would limit growth of the bacterial population through cell division.
Why would a compound that interferes with bacterial cell wall synthesis be useful for treating a bacterial infection? - It would prevent replication of DNA, and it would limit the spread of the infection. - It would limit growth of the bacterial population through cell division. - It would prevent the cells from becoming larger. - It would prevent replication of DNA.
It would limit growth of the bacterial population through cell division.
Why would a compound that interferes with bacterial cell wall synthesis be useful for treating a bacterial infection? - It would prevent replication of DNA. - It would prevent replication of DNA, and it would limit the spread of the infection. - It would prevent the cells from becoming larger. - It would limit growth of the bacterial population through cell division.
It would limit growth of the bacterial population through cell division.
At which stage of the cell cycle could you see sister chromatids with a microscope? - S - G1 - M - G2
M
Which of the answer choices is a characteristic of meiotic cell division? - The cells produced by meiosis are genetically identical. - Meiotic cell division ultimately results in the formation of two cells. - Meiotic cell division requires two rounds of DNA replication. - Meiotic cell division results in halving the number of chromosomes.
Meiotic cell division results in halving the number of chromosomes.
Which statement represents a misconception about sister chromatids? - Sister chromatids are formed when the prokaryotic circular chromosome attaches at the plasma membrane. - Sister chromatids are attached to each other at their centromeres. - Sister chromatids are formed in the S phase of the cell cycle when the chromosome undergoes replication. - Sister chromatids are identical or nearly identical DNA sequences. - Sister chromatids are also called homologous chromosomes.
Sister chromatids are formed when the prokaryotic circular chromosome attaches at the plasma membrane.
How must spindle microtubules attach to chromosomes during prometaphase of meiosis I? - Spindle microtubules from one pole must attach to both kinetochores in a pair of sister chromatids. - Spindle microtubules from one pole attach to one kinetochore, and spindle microtubules from the other pole attach to the other kinetochore in a pair of sister chromatids, just like in mitosis. - Microtubules attach to the chiasma. - Microtubules attach at the centrosomes. - Microtubules attach using their minus (slow assembling) ends.
Spindle microtubules from one pole must attach to both kinetochores in a pair of sister chromatids.
Suppose you analyze a time-lapse video of a cell under a microscope, and you observe what appears to be four chromatids tightly aligned along their lengths. Which of the answer choices is an interpretation of this observation? - The chromatids represent a bivalent and the cell is probably in Prophase I of meiosis. - The cell has completed S phase and is ready to begin cell division. - The chromatids are the result of crossing over prior to initiation of Prophase 1 of meiosis. - The cell is probably from a plant that has four sets of chromosomes, rather than only two sets.
The chromatids represent a bivalent and the cell is probably in Prophase I of meiosis.
There are laboratory techniques that allow researchers to determine the amount of DNA in cell nuclei. If you measure the amounts of DNA at the end of mitosis and at the end of meiosis, how do they compare to the starting cell (starting from prophase during mitosis and from prophase I during meiosis)? - The daughter cells at the end of mitosis have one-half the amount of DNA, and the daughter cells at the end of meiosis have one-half the amount of DNA. - The daughter cells at the end of mitosis have one-fourth the amount of DNA, and the daughter cells at the end of meiosis have one-half the amount of DNA. - The daughter cells at the end of mitosis have one-half the amount of DNA, and the daughter cells at the end of meiosis have one-fourth the amount of DNA.
The daughter cells at the end of mitosis have one-half the amount of DNA, and the daughter cells at the end of meiosis have one-fourth the amount of DNA.
There are laboratory techniques that allow researchers to determine the amount of DNA in cell nuclei. If you measure the amounts of DNA at the end of mitosis and at the end of meiosis, how do they compare to the starting cell (starting from prophase during mitosis and from prophase I during meiosis)? - The daughter cells at the end of mitosis have one-half the amount of DNA, and the daughter cells at the end of meiosis have one-half the amount of DNA. - The daughter cells at the end of mitosis have one-half the amount of DNA, and the daughter cells at the end of meiosis have one-fourth the amount of DNA. - The daughter cells at the end of mitosis have one-fourth the amount of DNA, and the daughter cells at the end of meiosis have one-half the amount of DNA.
The daughter cells at the end of mitosis have one-half the amount of DNA, and the daughter cells at the end of meiosis have one-fourth the amount of DNA.
Which of the answer choices is part of the process of binary fission in prokaryotes? - rearrangement of the microtubule cytoskeleton - separation of sister chromatids - condensation of chromosomes - formation of a new cell wall
formation of a new cell wall
Which of the answer choices is part of the process of binary fission in prokaryotes? - separation of sister chromatids - condensation of chromosomes - rearrangement of the microtubule cytoskeleton - formation of a new cell wall
formation of a new cell wall
What is the function of the centromere? - to organize the microtubules to form a spindle - to attach the DNA to the plasma membrane - to attach the chromosome to the spindle - to attach the sister chromatids to each other
to attach the sister chromatids to each other
What is the function of histone proteins? - to attach sister chromatids together - to connect chromosomes to the mitotic spindle - to organize the microtubules that make up the spindle - to package DNA in eukaryotic chromosomes
to package DNA in eukaryotic chromosomes
