Deck 14: Cellular Reproduction

Question 1

The stages through which a cell passes from one cell division to the next constitute the _________.

A)cell cycle
B)life cycle
C)biocycle
D)energy cycle
E)regeneration cycle

Answer 1

A

Question 2

Based on cell activities readily visible in the light microscope,there are two major cell cycle phases,________ and __________.

A)M phase,cytokinesis
B)interphase,cytokinesis
C)M phase,C phase
D)M phase,interphase
E)C phase,interphase

Answer 2

D

Question 3

Which cells typically have very short cell cycles on the order of less than 30 minutes?

A)cells in a cleaving frog embryo
B)mammalian liver tissue
C)mammalian muscle cells
D)both cells in a cleaving frog embryo and mammalian muscle cells
E)nerve cells

Answer 3

A

Question 4

Cells that have stopped dividing and are arrested in a stage preceding the initiation of DNA synthesis are said to be in a ______ state.

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

Question 5

The total length of the cell cycle of cells in a cell culture is 24 hours.M phase is found to be 1 hour,S phase is found to be 9 hours and G₂ is found to be 4.5 hours.How long is G₁?

A)24 hours
B)9)5 hours
C)9 hours
D)1 hour
E)4)5 hours

Question 6

Which of the cells below normally possess a relatively high level of mitotic activity?

A)stem cells of various adult tissues
B)hematopoietic stem cells that give rise to red and while blood cells
C)stem cells at the base of numerous epithelia that line the body cavities
D)the relatively unspecialized cells found near the tips of plant roots and stems
E)All of these are correct.

Question 7

What property below do stem cells not share with most cells?

A)They exhibit asymmetric cell division.
B)They do not replicate their DNA before cell division.
C)The two daughter cells have different properties or fates.
D)They exhibit symmetric cell division.
E)They exhibit asymmetric cell division and the two daughter cells have different properties or fates.

Question 8

What is the average length of M phase?

A)about 1 hour
B)about 10 minutes
C)about 10 hours
D)4 hours and 35 minutes
E)about a day

Question 9

Which cells typically have cell cycles lasting several months?

A)cells in a cleaving frog embryo
B)mammalian liver tissue
C)mammalian embryo cells
D)both cells in a cleaving frog embryo and mammalian embryo cells
E)nerve cells

Question 10

What is the average length of interphase?

A)It is exactly 10 hours in all cells.
B)It is 12 hours long.
C)There is not a good average since it depends on the cell type and conditions.
D)It may last up to a day.
E)On average,it lasts about 3 hours.

Question 11

What evidence suggests that a cell spends the majority of its time in interphase?

A)Interphase is more useful.
B)Only a small percentage of cells in a tissue or cell culture are seen to be in mitosis at any given time.
C)A large percentage of cells in a tissue or cell culture are seen to be in mitosis at any given time.
D)A moderate percentage of cells in a tissue or cell culture are seen to be in mitosis at any given time.
E)Mitosis is too intricate a process to last very long.

Question 12

Which part of the cell cycle is the most variable?

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

Question 13

DNA replication and the production of additional histones occur during what part of the cell cycle?

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

Question 14

The period in the cell cycle between the end of cell division and the beginning of DNA synthesis is called the _____ phase.

A)G1
B)S
C)G2
D)M
E)G0

Question 15

What types of non-stem cells also engage in asymmetric or unequal divisions?

A)formation of oocytes and polar bodies
B)formation of spermatogonia
C)division of red blood cells
D)division of B cells
E)division of liver cells

Question 16

What must happen in order for a cell to move to S phase from G₁?

A)It must divide.
B)It must generate an external signal.
C)It must receive a growth-promoting signal.
D)It must divide and receive a growth-promoting signal.
E)It must grow greatly.

Question 17

The separation of the entire cell and its cytoplasm into two daughter cells is known as _______.

A)meiosis
B)cytokinesis
C)chromokinesis
D)chromatosis
E)mitosis

Question 18

What stimulus can induce liver cells to proliferate?

A)interaction with an appropriate antigen
B)interaction with an appropriate antibody
C)surgical removal of part of the liver
D)a buildup of bile in the liver
E)glycogen buildup in the liver

Question 19

When do most of the preparations for mitosis occur,including such activities as DNA replication?

A)cytokinesis
B)M phase
C)interphase
D)telophase
E)enterophase

Question 20

The separation of duplicated chromosomes into two daughter nuclei is known as ________.

A)meiosis
B)cytokinesis
C)chromokinesis
D)chromatosis
E)mitosis

Question 21

What appears to be responsible for the tighter adhesion between chromosomes seen at centromeres rather than along the chromosome arms?

A)elevated phosphorylation
B)a kinase found at the centromere that phosphorylates cohesin
C)a phosphatase found at the centromere that removes phosphate groups from cohesin if they are added
D)a phosphatase found in the chromosome arms that removes phosphate groups from cohesin
E)a phosphatase found in the chromosome arms that adds phosphate groups to cohesin

Question 22

What activates condensin at the onset of mitosis?

A)Na⁺ ions
B)phosphorylation of several of its subunits by the Cdk-cyclin that drives cells from G₂ into mitosis
C)phosphorylation of several of its subunits by the Cdk-cyclin that drives cells from G₁ into mitosis
D)phosphorylation of several of its subunits by the Cdk-cyclin that drives cells from G₁ into S phase
E)dephosphorylation of several of its subunits by the Cdk-cyclin that drives cells from G₂ into mitosis

Question 23

What happens if any of the condensin proteins are removed from the frog egg extracts within which chromosome compaction can occur in vitro?

A)Compaction continues unabated.
B)Compaction occurs more quickly than normal.
C)Compaction is prevented.
D)The DNA expands further and fills the entire cell.
E)Compaction occurs but occurs more slowly.

Question 24

Once a fission yeast cell passes START,the cell is committed to replication.What is responsible for activating cdc2 at this time?

A)one or more G₁ cyclins
B)one or more G₂ cyclins
C)one or more S cyclins
D)one or more M cyclins
E)one or more G₀ cyclins

Question 25

What triggers the entry of a cell into mitosis?

A)the addition of inhibitory phosphate groups to Cdk1 by the Cdc25 phosphatase
B)the removal of inhibitory phosphate groups from Cdk1 by the Cdc25 phosphatase
C)the addition of inhibitory phosphate groups to Cdk1 by the Wee1 kinase
D)the removal of inhibitory phosphate groups from Cdk1 by the Wee1 kinase
E)the removal of phosphate groups from the Wee1 kinase

Question 26

What external stimulation is required by mammalian cells to progress through the cell cycle prior to reaching the restriction point?

A)presence of steroid hormones in their culture medium
B)presence of Na+ ions in their culture medium
C)presence of growth factors in their culture medium
D)no external stimulation is required
E)presence of vitamins in their culture medium

Question 27

What is responsible for holding sister chromatids together after replication? It holds the two chromatids together through G₂ and into mitosis.

A)compressin
B)cohesin
C)condensin
D)connexin
E)contractin

Question 28

How would you describe the orientation of the two centrioles of the centrosome relative to each other?

A)oriented at right angles
B)oriented in the same direction
C)obverse
D)reversed
E)converse

Question 29

In fission yeast cells,at which sites is replication initiated?

A)at randomly selected sites
B)at sites where histones bind
C)at sites where prereplication complexes have previously assembled
D)at sites where RNA polymerase binds
E)at sites that bind nucleosomes bind

Question 30

What disease can be defined as resulting from a breakdown in a cell's ability to regulate its own division?

A)multiple sclerosis
B)cancer
C)emphysema
D)diabetes
E)heart disease

Question 31

The first transition point in yeast cells that commits the cells to entering S phase occurs just before the end of ___ and is called _______.

A)G₂,START
B)G₁,MPF
C)G₂,MPF
D)G₁,BEGIN
E)G₁,START

Question 32

You are carrying out experiments in cell fusion by fusing together cells at different stages of the cell cycle.You then observe the behavior of each nucleus residing in the combined cytoplasm of the two cells.Which of the following responses would occur if you fused an S-phase cell to a cell in the M phase?

A)The nucleus from the M phase cell started to replicate its DNA.
B)The S-phase nucleus undergoes premature chromosomal condensation to form a set of elongated compacted chromosomes.
C)The M phase nucleus is affected in such a way that its compacted chromosomes decondense.
D)The chromatin in the S-phase nuclei is compacted,but pulverized chromosomal fragments form.
E)The S-phase nucleus undergoes premature chromosomal condensation; the compacted chromosomes are visibly doubled.

Question 33

As cells enter mitosis,their microtubules disassemble and then reassemble forming the mitotic spindle with a focus at the ________,a special animal cell microtubule-organizing structure.

A)kinetosome
B)centrosome
C)kinetochore
D)centromere
E)chromosome

Question 34

Mammalian cells pass through a point comparable to START during G₁,at which time they become committed to DNA replication and,ultimately,the completion of mitosis.What is this point called?

A)START
B)the restriction point
C)the limitation point
D)the commitment point
E)BEGIN

Question 35

What external stimulation is required by mammalian cells to progress through the cycle after they have passed the restriction point?

A)the presence of steroid hormones in their culture medium
B)the presence of Na⁺ ions in their culture medium
C)the presence of growth factors in their culture medium
D)no external stimulation is required after the restriction point is passed
E)the presence of vitamins in their culture medium

Question 36

What multiprotein complex has recently been shown to play a significant role in chromosome compaction?

A)compressin
B)condensin
C)elastin
D)loopin
E)mitosin

Question 37

The regulatory subunit of maturation-promoting factor ________.

A)transfers a phosphate group to certain serine and threonine residues of specific protein substrates
B)is called cyclin because its concentration rises and falls predictably as the cell cycle progresses
C)converts ATP to ADP
D)converts ADP to ATP
E)transfers a phosphate group to certain tyrosine residues of specific protein substrates

Question 38

When is a kinetochore assembled on the centromere?

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

Question 39

Movement past the transition point near the end of G₂ that moves cells on to mitosis requires cdc2 activation by _______.

A)Na⁺ ions
B)mitotic cyclins
C)ATP
D)Na⁺-K⁺ ATPase
E)mitotic chromatin

Question 40

At the outer surface of the centromere of each chromatid is a proteinaceous,buttonlike structure called the __________.

A)primary constriction
B)residence
C)kinetochore
D)proteasome
E)kinetosome

Question 41

What controls the progression of a cell from G₂ to M?

A)mitotic Cdk
B)synthetic Cdk
C)the spindle
D)chromosome compaction
E)mitotic Cpk

Question 42

What triggers the start of centrosome duplication?

A)phosphorylation of a centrosomal protein by ATPase
B)phosphorylation of a centrosomal protein by Cdk2
C)dephosphorylation of a centrosomal protein by Cdk2
D)dephosphorylation of a centrosomal protein by ATPase
E)phosphorylation of a centrosomal protein focal adhesion kinase

Question 43

What is an alternative to the classical view of the fate of the membranous portion of the nuclear envelope?

A)fragmentation into a population of small vesicles that disperse throughout the mitotic cell
B)absorption of the membranes of the nuclear envelope into the membranes of the Golgi complex
C)absorption of the membranes of the nuclear envelope into the membranes of the peroxisomes
D)absorption of the membranes of the nuclear envelope into the membranes of the ER
E)absorption of the membranes of the nuclear envelope into the membranes of the nucleoplasm

Question 44

What initiates the disassembly of the three major components of the nuclear envelope?

A)phosphorylation of key substrates by mitotic kinases,particularly cyclin B-Cdk1
B)dephosphorylation of key substrates by mitotic phosphatases,particularly cyclin B-Cdk1
C)a cascade begun by ATP synthase
D)phosphorylation of key substrates by mitotic phosphatases,particularly cyclin B-Cdk
E)methylation of key substrates by mitotic kinases,particularly cyclin B-Cdk1

Question 45

The start of centrosome duplication begins at the ______ transition.

A)M-G₁
B)G₁-S
C)S-G₂
D)G₂-M
E)G₁-M

Question 46

The process of centriole "replication" begins in the cytoplasm with the appearance of a small ________.

A)pericentriole
B)procentriole
C)precentriole
D)procentrosome
E)pericentrosome

Question 47

What apparently drives the separation of centrosomes?

A)motor proteins associated with microfilaments
B)motor proteins associated with adjacent microtubules
C)contraction of individual microfilaments
D)sliding of adjacent microfilaments over one another
E)contraction of adjacent microtubules

Question 48

The nuclear pore complexes are disassembled _________.

A)as the interactions between nucleoporin complexes are disrupted and the proteins dissociate into the surrounding medium
B)by depolymerization of the lamin filaments
C)as their integrity is disrupted mechanically as holes are torn in the complexes by cytoplasmic dyneins associated with the outer nuclear membrane
D)by cytoplasmic dyneins
E)by cytoplasmic microtubules and microfilamnets

Question 49

Even before cytokinesis has been completed,the two centrioles of a daughter cell disengage,an event that is triggered by the enzyme _________,which becomes activated late in mitosis.

A)invertase
B)centriolase
C)separase
D)disengagase
E)activase

Question 50

The current view of the fate of the ER during mitosis is that ________.

A)the ER network remains relatively intact during mitosis
B)the ER is broken into its component macromolecules during mitosis,but it is built up from scratch after mitosis
C)the ER is broken up into small vesicles that reassemble later
D)the ER becomes part of the Golgi complex during mitosis
E)the ER joins with mitochondria at the beginning of mitosis

Question 51

Microtubules are nucleated in cells with centrosomes in the vicinity of the centrosomes.Where do they nucleate in cells lacking centrosomes?

A)in the vicinity of the nucleolus
B)in the vicinity of the mitochondria
C)in the vicinity of the chromosomes
D)in the vicinity of the cell membrane
E)in the vicinity of the lysosomes

Question 52

The sunburst arrangement of microtubules that forms around each centrosome during early prophase is called a(n)________.

A)sunburst
B)arnost
C)aster
D)astral fiber
E)barrel

Question 53

What molecular motor has been implicated in the model of nuclear envelope dissolution that involves microtubules?

A)myosin
B)kinesin
C)dynein
D)calpain
E)calmodulin

Question 54

What is the event that begins prometaphase?

A)the complete compaction of the chromosomes
B)the disappearance of the nucleolus
C)the dissolution of the nuclear envelope
D)the reappearance of the nucleolus
E)the completion of the connection of chromosomes to the spindle

Question 55

The nuclear lamina are disassembled _________.

A)as the interactions between nucleoporin complexes are disrupted and the proteins dissociate into the surrounding medium
B)by depolymerization of the lamin filaments
C)as their integrity is disrupted mechanically as holes are torn in the complexes by cytoplasmic dyneins associated with the outer nuclear membrane
D)by cytoplasmic dyneins
E)by cytoplasmic microtubules and microfilaments

Question 56

As revealed by recent studies,which organelles do not seem to remain intact during mitosis?

A)mitochondria
B)Golgi complex
C)ER
D)peroxisomes
E)chloroplasts

Question 57

The integrity of the nuclear envelope is disrupted _________.

A)as the interactions between nucleoporin complexes are disrupted and the proteins dissociate into the surrounding medium
B)by depolymerization of the lamin filaments
C)as its integrity is disrupted mechanically as holes are torn into it by cytoplasmic dyneins associated with the outer nuclear membrane
D)by cytoplasmic kinesins
E)by cytoplasmic microtubules and microfilaments

Question 58

What are the three major components of the nuclear envelope?

A)nuclear pore complex,nuclear lemina,nuclear membranes
B)RER,nuclear lamina,Na+-K+ pump
C)nuclear pore complexes,nuclear lamina,nuclear membranes
D)mitotic kinases,nuclear lemina,nuclear pore complexes
E)phospholipids,nuclear pore complexes,nucleoplasm

Question 59

Which of the following is involved with the machinery that links kinetochores to dynamic microtubules?

A)motor proteins
B)a rod-shaped protein called Ndc80
C)the KMN network
D)curling microtubule protofilaments
E)All of these are correct.

Question 60

What allows the interaction between the mitotic spindle and the chromosomes to occur?

A)nuclear envelope breakdown
B)nucleosome breakdown
C)nucleolus breakdown
D)chromatin dissolution
E)chromosome condensation

Question 61

At what stage of meiosis are vertebrate eggs usually fertilized?

A)prophase II
B)metaphase I
C)interkinesis
D)metaphase II
E)anaphase I

Question 62

Which of the following is a multiprotein complex that acts primarily during interphase to ubiquitinate proteins and target them for destruction by a proteasome?

A)SCF
B)APC
C)anaphase promoting complex
D)both SCF and APC
E)proteasomal activating complex

Question 63

What is the first step in genetic recombination?

A)lengthening of the chromosomes
B)the introduction of single-stranded breaks in aligned DNA molecules
C)the introduction of double-stranded breaks in aligned DNA molecules
D)the accurate alignment of DNA molecules
E)the exchange of pieces of DNA between homologous chromosomes

Question 64

In the human female,after their long arrest,when do oocytes resume meiosis?

A)just prior to their ovulation
B)prior to birth
C)between the ages of 4 and 6
D)at the end of each menstrual cycle
E)just after birth

Question 65

Which stage of mitosis starts as sister chromatids split apart and begin to move toward opposite poles?

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

Question 66

___________ in males and _______ in females undergo mitosis giving rise to the cells that will carry out meiosis and eventually produce mature gametes.

A)Oogonia,spermatogonia
B)Spermatogonia,oocytes
C)Spermatogonia,oogonia
D)Oogonia,spermatocytes
E)Spermatocytes,oocytes

Question 67

What is the name of the process during which chromosome number is reduced so that each cell has a haploid number of chromosomes?

A)mitosis
B)meiosis
C)cytokinesis
D)sexual differentiation
E)meitosis

Question 68

Organisms in which meiotic divisions are closely linked to gamete formation,as in the case where meiosis occurs just prior to the differentiation of the spermatozoa,exhibit ___________.

A)initial meiosis
B)terminal meiosis
C)zygotic meiosis
D)sporic meiosis
E)intermediate meiosis

Question 69

How does securin get its name?

A)Securin secures chromosomes to the cell membrane.
B)Securin secures the attachment between sister chromatids.
C)Securin determines which substances can enter the nucleus and which cannot.
D)Securin secures the binding of the kinetochore to the chromosome.
E)Securin attaches kinetochores to the spindle.

Question 70

When do homologous regions of DNA in homologous chromosomes first make contact?

A)leptotene
B)zygotene
C)pachytene
D)diplotene
E)diakinesis

Question 71

What occurs during pairing of chromosomes in prophase of meiosis I that increases genetic variability?

A)further condensation of chromosomes
B)genetic recombination between homologous chromosomes
C)lots of mutations
D)chromosomes lose lots of fragments
E)gene duplication

Question 72

On occasion,the two kinetochores of sister chromatids will become attached to microtubules from the same spindle pole; this condition is referred to as ________.

A)osteosarcoma
B)systolic attachment
C)syntelic attachment
D)opposite chromatid attachment
E)synthetisism

Question 73

Cells that have a single set of chromosomes are said to have a _______ number of chromosomes; cells that contain two full sets of paired chromosomes are said to have a ______ number of chromosomes.

A)diploid,haploid
B)haploid,diploid
C)diploid,diploid
D)haploid,haploid
E)monoploid,polyploidy

Question 74

In the human female,when is prophase I of meiosis initiated?

A)at puberty
B)prior to birth
C)between the ages of 4 and 6
D)at the beginning of each menstrual cycle
E)at the end of each menstrual cycle

Question 75

What may be the purpose of the clustering of telomeres in a variety of eukaryotic cells that presumably causes chromosomes to look like a flower bouquet?

A)It may terminate synapsis.
B)It may facilitate chromosome alignment in preparation for synapsis.
C)It may prevent chromosome alignment until synapsis begins.
D)It may spread chromosomes out in preparation for synapsis.
E)It may start the dissolution of the nuclear envelope.

Question 76

What is the name of the enzyme that responds to the lack of bipolar tension when both chromatids are attached to microtubules from the same spindle pole and helps to correct the abnormality?

A)streptokinase
B)Aurora B kinase
C)Cdc kinase
D)protein kinase
E)tubulin kinase

Question 77

By what process are gametes produced from a gametophyte?

A)meiosis
B)cytokinesis
C)mitosis
D)fission
E)replication

Question 78

During what stage do studies of mice and yeast cells suggest that DNA breaks leading to recombination begin?

A)pachytene
B)leptotene
C)diakinesis
D)zygotene
E)diplotene

Question 79

What usually happens to vertebrate eggs immediately after they have been fertilized?

A)Cytokinesis begins.
B)They start to grow.
C)Mitosis begins.
D)Meiosis is completed.
E)The egg sheds lots of cytoplasm.

Question 80

What word below characterizes the adult generation that is produced after zygotic meiosis?

A)diploid
B)haploid
C)enormous
D)polyploid
E)aneuploid