1. DNA: Directs cell activity
Gene: a segment of DNA that transmits information.
Chromosome: a single DNA molecule and its associated proteins.
Chromatid: copy of a chromosome.

2. Mitosis
2012

3. Centromere – area where the chromatids of a chromosome are attached
Mitosis - General
Division of the cell nucleus
Chromosomes have replicated & are visible
# of centromeres = # of chromosomes
Centromere – area where the chromatids of a chromosome are attached

4. Mitosis – General Cont’d
4. Each daughter cell receives its own copy of the parent cell’s DNA
5. Occurs in body cells – somatic cells

5. Interphase
G1 Phase the cell grows & carries out routine functions. (increase in size)
S Phase DNA is duplicated/copied.
G2 Phase Cell prepares for mitosis.
Cell grows & produces additional organelles & cytoplasm.

6. Interphase Plant Cell Animal Cell
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7. are present in this cell?
Prophase
How many chromatids
are present in this cell?
Chromatin condenses and forms chromosomes.
Pairs of sister chromatids are joined at the centromere.
Nuclear membrane breaks down and disappears.
Centrioles (in animal cells) split and move toward opposite poles of the cell.
A spindle forms fibers that organize themselves around the centrioles and attach themselves to the centromere.
Spindle Fibers are thread-like structures (microtubles) that help separate chromosomes during mitosis .

8. Prophase Plant Cell Animal Cell Spindle fibers Centrioles
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9. about the spindle fibers and chromosomes?
Metaphase
Chromosomes line up at the equator of the cell.
Each centromere is connected to a spindle fiber.
What do you notice
about the spindle fibers and chromosomes?
They are attached
to the centromeres.

10. Metaphase Plant Cell Animal Cell
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11. Anaphase
Sister chromatids separate at the centromere & are pulled by spindle fibers to opposite ends of the cell.
Now they again chromosomes.

12. Anaphase Plant Cell Animal Cell
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13. Telophase Chromosomes gather at opposite ends of cell.
Begin to unravel…back to chromatin!
Nuclear membrane and nucleolus reform
Mitosis is now complete!
All the remains is the division!

14. Telophase Plant Cell Animal Cell
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15. Cytokinesis Daughter Cells Not part of mitosis.
Cytoplasm divide in half.
Each daughter cell has an identical set of chromosomes
Plants – cell plate separates the two new cells
Animals – cleavage furrow pinches the two new cells a part; centrioles double
Daughter Cells

16. Animal Mitosis -- Review
Interphase                                                             
Prophase                                                             
Metaphase                                                             
Anaphase                                                             
Telophase                                                             

17. Plant Mitosis -- Review
Interphase                                                             
Prophase                                                             
Metaphase                                                             
Anaphase                                                             
Telophase