Deck 10: Cell Division and Mitosis

Question 1

Compared to the parent cell, each of two daughter cells that result from normal mitotic division contains ____ chromosomes and is genetically ____.

A) the same number of; different
B) the same number of; identical
C) half the number of; different
D) half the number of; identical
E) double the number of; identical

Answer 1

B

Question 2

How many unique chromosomes does an organism with a chromosome number of 4 n =32 have? Assume that none of these are sex chromosomes, and do not count any duplicate homologous chromosomes in this number.

A) 4
B) 8
C) 16
D) 32
E) 64

Answer 2

B

Question 3

The tight packing of chromatin into the chromosomes visible during nuclear division is possible due to links between ____ proteins.

A) Cdk
B) H1 histone
C) H3 histone
D) H4 histone
E) nonhistone

Answer 3

B

Question 4

What is the role of nonhistone proteins in the nucleus?

A) to regulate nuclear envelope formation
B) to facilitate nuclear transportation
C) to provide additional chromosomal structure
D) to disassemble the nuclear envelope
E) to aid in microtubule formation during mitosis

Question 5

The ____ genome was the first eukaryotic genome to be sequenced.

A) Escherichia coli
B) Caenorhabditis elegans
C) Drosophila melanogaster
D) Saccharomyces cerevisiae
E) Schizosaccharomyces pombe

Question 6

If a cell has 36 chromosomes at the beginning of G₁, how many chromosomes will be present at the end of G₂?

A) 36
B) 18
C) 72
D) 64
E) 44

Question 7

At the conclusion of mitosis, each daughter cell has ____.

A) twice the amount of DNA and half the cytoplasm of the parent cell
B) DNA identical to the parent cell
C) half the DNA and half the cytoplasm found in the parent cell
D) twice the cytoplasm and the same amount of DNA as the parent cell
E) DNA genetically different from the parent cell

Question 8

Generally, which phase of the cell cycle varies the most in length?

A) G₁
B) S
C) G₂
D) M
E) All phases are the same length among cells

Question 9

The cells produced by mitotic divisions are considered to be ____ the original cell.

A) smaller versions of
B) genetically unique from
C) clones of
D) mutants of
E) plasmids of

Question 10

At the conclusion of S phase, a diploid cell with 40 chromosomes will have ____ chromosomes and _____ sister chromatids.

A) 20; 40
B) 20; 20
C) 40; 40
D) 40; 80
E) 80; 80

Question 11

Replication of DNA occurs during ____.

A) S phase
B) G₁phase
C) G₀phase
D) prophase
E) cytokinesis

Question 12

Once human nerve cells become mature, they normally exit the cell cycle and remain in ____.

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

Question 13

If a diploid cell with 40 chromosomes undergoes meiosis, each daughter nuclei will have ____ chromosomes.

A) 10
B) 20
C) 40
D) 60
E) 80

Question 14

A plant cell with three sets of chromosomes is ____.

A) haploid
B) diploid
C) triploid
D) tetraploid
E) hexaploid

Question 15

The separation of duplicated chromosomes into two new nuclei is known as ____.

A) mitosis
B) cytokinesis
C) binary fission
D) meiosis
E) fertilization

Question 16

Where is the centromere found?

A) position where metaphase chromosomes align
B) location where the mitotic spindle forms
C) central region of a chromosome where the spindle microtubules attach
D) location where chromosomes cluster during telophase
E) center of the cell where the nucleus is found during prophase

Question 17

If a cell contains 84 sister chromatids at metaphase of mitosis, how many chromosomes will be present in each nucleus in late telophase?

A) 168
B) 84
C) 42
D) 21
E) cannot be determined from the information given

Question 18

Early in mitosis, chromatin condenses. Which process takes place more easily as a result?

A) disappearance of the nuclear envelope
B) replication of DNA
C) orderly distribution of DNA into the two new nuclei
D) formation of the mitotic spindle
E) disintegration of nucleoli

Question 19

A somatic cell divides to form two genetically identical daughter cells during mitosis. Prior to mitosis, what must occur?

A) The cell must replicate its DNA.
B) The cell must first be fertilized.
C) The nucleus must divide.
D) Chromatids must be separated.
E) The nuclear envelope must disintegrate.

Question 20

Loosely packed regions of DNA associated with histones are called ____.

A) euchromatin
B) heterochromatin
C) chromosomes
D) nucleosomes
E) 30-nm chromatin fibers

Question 21

Certain human cell types, such as skeletal muscle cells, have several nuclei per cell. Based on your understanding of mitosis, how could this happen?

A) The cell undergoes repeated cytokinesis but not mitosis.
B) The cell undergoes repeated mitotic divisions with concomitant cytokinesis.
C) The cell undergoes repeated mitotic divisions but not cytokinesis.
D) The cell undergoes anaphase twice before entering telophase.
E) The cell goes through multiple S phases before entering mitosis.

Question 22

Answer the following questions using the accompanying figure.
Figure 10.1
Identify the stage of mitosis shown in panel C.

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

Question 23

Cytokinesis typically begins during which stage of mitosis?

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

Question 24

Organisms that reproduce asexually usually do so through the process of ____.

A) mitosis
B) meiosis
C) gametogenesis
D) spore formation
E) fertilization

Question 25

Karyotype analyses are performed on cells in ____ of mitosis.

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

Question 26

Which sequence of the cell cycle is correct?

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

Question 27

Colchicine, a chemical extracted from the autumn crocus (C olchicum autumnale ), inhibits the formation of microtubules. Mitotic cells exposed to colchicine will therefore be arrested at ____.

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

Question 28

Answer the following questions using the accompanying figure.
Figure 10.1
Identify the stage of mitosis shown in panel B.

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

Question 29

Embryonic development begins with a single egg fertilized by a single sperm, forming a zygote which then divides by mitosis. How many cells are present in the embryo at the conclusion of four mitotic divisions?

A) 2
B) 4
C) 8
D) 16
E) 32

Question 30

During which phase(s) of mitosis are chromosomes composed of two sister chromatids?

A) prophase and prometaphase only
B) prophase, prometaphase, and metaphase
C) prophase, prometaphase, metaphase, and anaphase
D) anaphase and telophase only
E) all phases of mitosis

Question 31

During ____, microtubules disassemble, pulling the chromatids to the ends of the spindle.

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

Question 32

Chromosomes are in a condensed form at which stage(s) of the cell cycle?

A) prophase only
B) prophase and metaphase
C) interphase
D) all stages of interphase and mitosis
E) throughout mitosis until late telophase

Question 33

Chromatin condenses into chromosomes and the mitotic spindle begins to form during ____.

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

Question 34

Answer the following questions using the accompanying figure.
Figure 10.1
Identify the stage of mitosis shown in panel D.

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

Question 35

Chromosomes decondense into chromatin at which point in the cell cycle?

A) at the beginning of S phase
B) at the end of interphase
C) at the beginning of prophase
D) at the beginning of metaphase
E) at the end of telophase

Question 36

Answer the following questions using the accompanying figure.
Figure 10.1
Identify the stage of mitosis shown in panel A.

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

Question 37

Answer the following questions using the accompanying figure.
Figure 10.1
Identify the stage of mitosis shown in panel E.

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

Question 38

When plants are produced by cloning, which process is most directly involved?

A) mitotic cell division
B) binary fission
C) meiotic cell division
D) gamete production
E) budding

Question 39

The mitotic spindle is primarily composed of ____.

A) actin
B) intermediate filaments
C) microtubules
D) keratin
E) motor proteins

Question 40

Which statement best describes the difference between cell division in plant and animal cells?

A) Cytokinesis occurs by formation of a cleavage furrow in animal cells, but not plant cells.
B) Cytokinesis occurs by formation of a cleavage furrow in plant cells, but not animal cells.
C) Centrosomes play an important role in spindle formation in plant cells, but not in animal cells.
D) Chromosome replication occurs during interphase in animal cells, while in plant cells, replication occurs when the nuclear envelope disintegrates.
E) Animal cells divide via the cell cycle whereas plant cells divide by binary fission.

Question 41

Binding of ____ activates proteins involved in DNA replication.

A) mitotic cyclins to mitotic Cdks
B) S-phase cyclins to S-phase Cdks
C) G1 cyclins to G1 Cdks
D) G1/S cyclins to G1/S Cdks
E) the MPF

Question 42

A cell is committed to progressing through the cell cycle through to mitosis once it transitions from ____.

A) G₂to prophase
B) G₁to G₀
C) G₁to S
D) S to G₂
E) telophase to cytokinesis

Question 43

In order to understand how chromosomes move during anaphase of mitosis, researchers tagged ____ with a fluorescent label before photobleaching the cell and examining chromosomal movement under a microscope.

A) DNA
B) kinetochore microtubules
C) nonkinetochore microtubules
D) histones
E) motor proteins

Question 44

The microtubules making up the mitotic spindle attach to specialized structures called ____ that are found in the centromere region of the chromosome.

A) nucleosomes
B) centrosomes
C) kinetochores
D) chromatids
E) centrioles

Question 45

Progression through the phases of the cell cycle is regulated by fluctuating concentrations of ____.

A) microtubules
B) actin
C) cyclins
D) cyclin-dependent kinases
E) histones

Question 46

Duplicated centrioles move to opposite poles of a(n) ____ cell during ____ of the cell cycle.

A) animal; prophase
B) plant; prophase
C) animal; metaphase
D) plant; metaphase
E) both animal and plant cells; prophase

Question 47

Contact inhibition is an important mechanism for maintaining cell growth in developed organs and tissues. As long as the cells maintain contact with each other, they remain in ____ and are prevented from dividing.

A) prophase
B) G₁
C) G₂
D) G₀
E) S

Question 48

When growth factors bind to receptors on the cell surface, the signaling cascade will ____.

A) initiate cell growth
B) prevent cell division
C) trigger cell death
D) cause the cells to enter the G₀state
E) trigger mitosis without the other stages of the cell cycle

Question 49

If a dividing cell had no functional G1/S Cdk protein, the cell would not be able to ____.

A) phosphorylate cyclins
B) transcribe the Cdk gene
C) enter S phase
D) translate cyclin mRNA
E) degrade cyclins

Question 50

The microtubule organizing center (MTOC) of an animal cell is an identifiable structure known as the ____.

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

Question 51

The nucleosome core particle is made up of ____.

A) two molecules each of H2A, H2B, H3, and H4
B) one molecule each of H2A, H2B, H3, and H4
C) two molecules each of H1, H2, H3, and H4
D) one molecule each of H1, H2, H3, and H4
E) six proteins

Question 52

Addition of mitosis-promoting factor (MPF) to germinal cells in the skin arrested in G₂leads the cells to ____.

A) stop dividing
B) enter prophase
C) undergo cytokinesis without mitosis
D) die
E) remain arrested in G₂

Question 53

Research conducted by G.J. Gorbsky and colleagues suggests that during anaphase, chromosomes move as a consequence of ____.

A) a combined action of actin and microtubules
B) the disassembly of kinetochore microtubules
C) the movement of kinetochore microtubules
D) constriction of the contractile protein actin
E) sliding over or along kinetochore microtubules

Question 54

What is the role of Cdks?

A) to add phosphate groups to target proteins
B) to check for proper attachment of spindle fibers to chromosomes
C) to remove phosphate groups from cyclins
D) to arrest the cell cycle
E) to allow the cell cycle to work forward or backward

Question 55

One of the three internal cell cycle checkpoints occurs during ____ and monitors ____.

A) the G₁/S transition; mitotic spindle integrity
B) late S phase; the presence of DNA damage
C) the G₂/M transition; the presence of DNA damage
D) the G₂/M transition; mitotic spindle integrity
E) anaphase; the presence of DNA damage

Question 56

If a given protein's level peaks early in G₁, but is absent before the G₂transition, what can be inferred about its possible role in regulating the cell cycle?

A) This protein inhibits S-phase Cdks.
B) This protein activates S-phase Cdks.
C) This protein inhibits G1/S Cdks.
D) This protein activates G1/S Cdks.
E) This protein is involved in DNA synthesis.

Question 57

Contact inhibition is best explained by which statement?

A) Contact between neighboring cells triggers reactions leading to inhibition of mitosis.
B) As neighboring cells become more tightly packed together, their size is restricted and cytokinesis can no longer occur.
C) As cell number increases, the protein kinases they produce compete with neighboring cells, inhibiting mitosis.
D) As cell number increases, the level of waste products increases, consequently slowing metabolism leading to mitosis.
E) As cell number increases, size restrictions inhibit protein synthesis.

Question 58

The microtubules of the mitotic spindle originate from the ____ in both plant and animal cells.

A) microtubule organizing centers (MTOCs)
B) centromere
C) chromatid
D) centriole
E) centrosome

Question 59

During the mitotic spindle checkpoint, ____.

A) cells are in anaphase
B) cells arrest if chromosomes are attached properly to the mitotic spindle
C) cells become irreversibly committed to S phase
D) proper spindle attachment to chromosomes is assessed
E) cells enter G₀

Question 60

Centriole replication occurs during ____.

A) G₁phase
B) S phase
C) G₂phase
D) prophase
E) telophase

Question 61

Which statement characterizes cancer cells?

A) Mitosis in cancer cells is strictly regulated.
B) Cancer cells form tumors that adhere strongly to surrounding tissues.
C) Cancer cells display uncontrolled cell division.
D) Tumors formed by cancer cells remain encapsulated and only grow in one location.
E) Cancer cells behave like normal cells.

Question 62

Most cancers require at least two mutations: 1) one in an oncogene, which encodes proteins that trigger cell division, and 2) one in a tumor suppressor gene, whose protein products, in their unmutated form, play a key role in preventing the cell cycle from progressing if the DNA is damaged or in the absence of specific cues. Which class of proteins might be considered tumor suppressors?

A) Cdk inhibitors
B) cyclins
C) growth factor receptors
D) microtubules
E) transcription factors

Question 63

Oncogenes are often ____.

A) mutant forms of cell cycle genes
B) normal forms of cell cycle genes
C) needed for normal cells to metastasize
D) required for normal contact inhibition of cells
E) not involved in cell division

Question 64

Bacterial cells typically have ____ while eukaryotic cells have ____.

A) a single circular chromosome; many linear chromosomes
B) several circular chromosomes; many linear chromosomes
C) one linear chromosome; many circular chromosomes
D) two circular chromosomes; numerous circular chromosomes depending on the species
E) numerous circular chromosomes depending on the species; many linear chromosomes

Question 68

Replication of a bacterial chromosome begins at a specific region called the ____.

A) ter
B) replication fork
C) beg
D) ori
E) rep

Question 69

Histones are positively charged proteins that complex with DNA in eukaryotic chromosomes.

Question 70

Explain how the non-kinetochore microtubules lead to the elongation of the cell during anaphase.

Question 71

Some bacteria produce the enzyme β-lactamase, which results in resistance to certain antibiotics such as penicillin. Since these same organisms reproduce asexually, they produce offspring that ____.

A) can be killed by penicillin
B) have an abnormally high rate of mutation
C) are resistant to penicillin
D) have variable numbers of chromosomes
E) can make penicillin

Question 72

Comparison of a cancer cell to a normal cell reveals that ____.

A) only cancer cell growth is limited by contact inhibition
B) only normal cell growth is limited by contact inhibition
C) cancer cells cannot metastasize, while normal cells can
D) regulation of mitosis is strictly regulated in cancer cells, but not in normal cells.
E) cancer cells remain adherent to other cells, while normal cells do not

Question 73

What is the purpose of mitosis in living organisms?

Question 74

During prokaryotic cell division, two chromosomes separate and are distributed to the two ends of the cell by ____.

A) the action of the mitotic spindle
B) an unknown mechanism
C) attachment to actin
D) attachment to separating membrane regions
E) formation of a newly made cell wall

Question 75

Vinblastine, a chemotherapeutic drug used to treat breast and testicular cancers, interferes with the assembly of microtubules. Speculate how this drug works to inhibit cancer cell growth.

A) Vinblastine inhibits transition from G₁to S.
B) Vinblastine inhibits transition from S to G₂.
C) Vinblastine inhibits cytokinesis.
D) Vinblastine disrupts mitotic spindle formation and consequently mitosis.
E) Vinblastine inhibits cyclin production.

Question 76

What are the two main features of prokaryotic binary fission?

Question 77

The evolution of binary fusion solved the mechanical problems associated with distributing long DNA molecules without breakage.

Question 78

Experiments that led to the understanding of cell cycle control were performed on yeast.

Question 79

Binary fission ____.

A) is thought to have evolved from mitosis
B) is involved in gamete formation
C) results in the production of two identical daughter cells
D) requires spindle formation
E) is important for eukaryotic cell growth

Question 80

An organism with a chromosome number of n =7 is said to be haploid.