(Cytokinesis often, but not always, accompanies telophase.)
(The chromatin fibers become discrete chromosomes.)
(During anaphase, sister chromatids separate and daughter chromosomes migrate to opposite poles.)
(Attachment of spindle fibers to kinetochores is one of the events of pro metaphase.)
(encompasses both mitosis and cytokinesis)
B. At this point, cell commits to go through the cycle.
C. DNA replicates
D. Centrosome replicates
E. Mitotic spindle begins to form.
F. Cell divides, forming two daughter cells.
In the G2 phase, the centrosome replicates.
In early M phase, the centrosomes move away from each other toward the poles of the cell, in the process organizing the formation of the mitotic spindle.
At the end of the M phase when mitosis is complete, the cell divides (cytokinesis), forming two genetically identical daughter cells.
2. N N N Y Y
3. N Y Y Y Y
Similarly, the cellular DNA content doubles in the S phase when the DNA replicates. However, the cell’s DNA content does not return to its normal (undoubled) levels until after cytokinesis is complete and two daughter cells have formed.
The condensation state of the DNA is not related to the presence or absence of sister chromatids. The DNA condenses in prophase and remains condensed until after the sister chromatids separate and the new daughter cells begin to form. In late telophase/cytokinesis, the emphasis shifts to cell growth and DNA replication for the next cell cycle. For these processes to occur, the DNA needs to be de-condensed so it is accessible to the cellular machinery involved in transcription.
2. Will the sister chromatids separate from each other? (yes)
3. Will the chromosomes move to the poles of the cell? (no)
*Chromosome separation begins at the origin of replication on DNA.
* Before separation, duplicated chromosomes condense.
* Nuclear envelope fragments, permitting chromosome separation.
* 2 copies of the duplicated chromosome are attached at their centromeres before separation.
Both Bacteria and Eukariotes:
* Chromosomes replicate before cell division.
* Replicated chromosomes separate by attaching to some other structural feature of the cell.
*The cell plate consists of the plasma membrane and cell wall that will eventually separate the two daughter cells.
(A diet high in fat increases the risk of both colon and breast cancer.)
(All of these substances can cause cancer.)