Bio 101 Test 3 Meiosis and Mitosis
correct 100%
Eukaryotic Cell Cycle - ANSWERG1 Phase, S Phase, G2 Phase and M Phase
G1 Phase - ANSWERFirst gap phase, period in a cell's life when it will be committed to
divide, they may accumulate molecular changes than can cause it to progress through
the rest of the cell cycle; cell growth typically occurs during this phase
S Phase - ANSWERSynthesis of DNA, genetic material; during S phase, the
chromosomes are replicated and the two copies are joined together and referred to as a
pair of sister chromatids; when S phase is completed, the cell will have twice as many
chromatids as chromosomes
G2 Phase - ANSWERSecond Gap Phase, when a cell synthesizes proteins that are
necessary for chromosome sorting and cell division; this prepares the cell for the last
phase of the cell cycle - some cell growth may occur
G0 Phase - ANSWERWhen a cell can no longer replicate
M Phase - ANSWERMitosis and Cytokinesis
Mitosis - ANSWERThe purpose of mitosis is to divide one cell nucleus into two nuclei,
distributing the duplicated chromosomes so that each daughter cell will have the same
complement of chromosomes; the replicated chromatids are separated and sorted so
each daughter cell will receive 46 chromosomes
Cell Checkpoints - ANSWERCritical regulatory points in a eukaryotic cell. At these
check points, a variety of proteins act as sensors to determine if a cell is in the proper
condition to divide.
Cyclins - ANSWERA Cell Checkpoint; a protein that is responsible for advancing a cell
through the phases of the cell cycle by binding to a cyclin-dependent, kinase
Cyclin-Dependent Kinase (CDK) - ANSWERA protein responsible for advancing a cell
through phases of the cell cycle; it's function is dependent on the binding of the cyclin
Mitotic Spindle - ANSWERThe structure that is responsible for organizing and sorting
the chromosomes during cell division
Centrosome - ANSWERRegions referred to as microtubule organizing center. A single
one duplicates during interphase (G1, G2 and S phase) - each organizes the
construction of the microtubules by rapidly polymerizing tubulin proteins
, Centriole - ANSWERFound in animal cells, two of them make up a centrosome
Polar Microtubules - ANSWERCalled interpolar microtubules, project into the region
between the tubules. Polar microtubules overlap eachother and play a role in the
separation of the two poles
Astral Microtubules - ANSWERExtend away from the chromosomes and are important
for positioning the spindle apparatus in the cell
Kinetochore Microtubules - ANSWERAttached to kinetochores which are bound to the
centromere of each chromosome
Phases of Mitosis - ANSWERProphase, Prometaphase, Metaphase, Anaphase,
Telophase
Prophase - ANSWERThe chromosomes have already repilicated to produce 12
chromatids. As it proceeds, the nuclear envelop begins to dissociate into small vesicles
and the chromatids condense into a highly compacted structures that are readly visible
by light microscopy
Prometaphase - ANSWERThe nuclear envelop completely fragments into small
vesicles, the centrosomes move apart and demarcate the two poles; the spindle fibers
can interact with sister chromatids
Metaphase - ANSWERThe sister chromatids align on the metaphase plate; the
chromatids can then be equally distributed between the two daughter cells
Anaphase - ANSWERThe connections between the pairs of sister chromatids are
broken. Each chromatid, now an individual chromosome, is linked to only one of the two
poles by one or more kinetochore microtubules. As anaphase proceeds, the kinetochore
microtubules shorten, pulling the chromosomes toward the pole to which they are
attached. The two poles move further away from each other
Telophase - ANSWERThe chromosomes have reached their prospective poles and
decondense. The nuclear envelope now reforms to produce two separate nuclei. The
two nuclei contain 6 chromosomes each
Cytokinesis - ANSWERWhere the nuclei are segregated into two daughter cells
Cleavage Furrow - ANSWERConstricts like a drawstring to separate cells -- only in
animal cells
Cell plate - ANSWERVesicles from the golgi apparatus move along microtubules to the
center of the cell and coalesce to form this -- this then forms the cell wall between the
two daughter cells -- only in plant cells
correct 100%
Eukaryotic Cell Cycle - ANSWERG1 Phase, S Phase, G2 Phase and M Phase
G1 Phase - ANSWERFirst gap phase, period in a cell's life when it will be committed to
divide, they may accumulate molecular changes than can cause it to progress through
the rest of the cell cycle; cell growth typically occurs during this phase
S Phase - ANSWERSynthesis of DNA, genetic material; during S phase, the
chromosomes are replicated and the two copies are joined together and referred to as a
pair of sister chromatids; when S phase is completed, the cell will have twice as many
chromatids as chromosomes
G2 Phase - ANSWERSecond Gap Phase, when a cell synthesizes proteins that are
necessary for chromosome sorting and cell division; this prepares the cell for the last
phase of the cell cycle - some cell growth may occur
G0 Phase - ANSWERWhen a cell can no longer replicate
M Phase - ANSWERMitosis and Cytokinesis
Mitosis - ANSWERThe purpose of mitosis is to divide one cell nucleus into two nuclei,
distributing the duplicated chromosomes so that each daughter cell will have the same
complement of chromosomes; the replicated chromatids are separated and sorted so
each daughter cell will receive 46 chromosomes
Cell Checkpoints - ANSWERCritical regulatory points in a eukaryotic cell. At these
check points, a variety of proteins act as sensors to determine if a cell is in the proper
condition to divide.
Cyclins - ANSWERA Cell Checkpoint; a protein that is responsible for advancing a cell
through the phases of the cell cycle by binding to a cyclin-dependent, kinase
Cyclin-Dependent Kinase (CDK) - ANSWERA protein responsible for advancing a cell
through phases of the cell cycle; it's function is dependent on the binding of the cyclin
Mitotic Spindle - ANSWERThe structure that is responsible for organizing and sorting
the chromosomes during cell division
Centrosome - ANSWERRegions referred to as microtubule organizing center. A single
one duplicates during interphase (G1, G2 and S phase) - each organizes the
construction of the microtubules by rapidly polymerizing tubulin proteins
, Centriole - ANSWERFound in animal cells, two of them make up a centrosome
Polar Microtubules - ANSWERCalled interpolar microtubules, project into the region
between the tubules. Polar microtubules overlap eachother and play a role in the
separation of the two poles
Astral Microtubules - ANSWERExtend away from the chromosomes and are important
for positioning the spindle apparatus in the cell
Kinetochore Microtubules - ANSWERAttached to kinetochores which are bound to the
centromere of each chromosome
Phases of Mitosis - ANSWERProphase, Prometaphase, Metaphase, Anaphase,
Telophase
Prophase - ANSWERThe chromosomes have already repilicated to produce 12
chromatids. As it proceeds, the nuclear envelop begins to dissociate into small vesicles
and the chromatids condense into a highly compacted structures that are readly visible
by light microscopy
Prometaphase - ANSWERThe nuclear envelop completely fragments into small
vesicles, the centrosomes move apart and demarcate the two poles; the spindle fibers
can interact with sister chromatids
Metaphase - ANSWERThe sister chromatids align on the metaphase plate; the
chromatids can then be equally distributed between the two daughter cells
Anaphase - ANSWERThe connections between the pairs of sister chromatids are
broken. Each chromatid, now an individual chromosome, is linked to only one of the two
poles by one or more kinetochore microtubules. As anaphase proceeds, the kinetochore
microtubules shorten, pulling the chromosomes toward the pole to which they are
attached. The two poles move further away from each other
Telophase - ANSWERThe chromosomes have reached their prospective poles and
decondense. The nuclear envelope now reforms to produce two separate nuclei. The
two nuclei contain 6 chromosomes each
Cytokinesis - ANSWERWhere the nuclei are segregated into two daughter cells
Cleavage Furrow - ANSWERConstricts like a drawstring to separate cells -- only in
animal cells
Cell plate - ANSWERVesicles from the golgi apparatus move along microtubules to the
center of the cell and coalesce to form this -- this then forms the cell wall between the
two daughter cells -- only in plant cells
