Transcript Mitosis_Teacher

Mitosis: The Mystery of
Cell Division
Objectives
When you complete this program you should be
able to:
1. Define the term Mitosis.
2. List and describe the stages of mitosis.
3. Identify cells in various stages of
the cell cycle using a microscope.
Why is Mitosis Necessary?
1.
The parent cell is too fat (too much
volume) compared to its skin
(surface area)
2.
Wastes do not exit quickly
3.
Nutrients do not enter quickly
4.
Essentially – divide of DIE!
Cell Cycle
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Cell Cycle can
be defined as
the life span of
the cell.
The cell cycle
consists of…
1.
2.
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Interphase
Mitosis
Remember
IPMAT!
IPMAT – in the order of
the letters
Division is Vital
to Survival
Interphase
1. Cell gets fat, swells.
2. It madly copies its
DNA in this phase in
preparation for the
inevitable cell division
Prophase
1. Centrioles go to the POLES or ends of the cell
2. Nuclear membrane begins to dissolve
3. Centrioles start casting out MITOTIC SPINDLE or NET
Metaphase – think “M” for MIddle
1. Chromosomes line
up in the middle of
the cell
2. Note that each
chromosome has
doubled and has two
pairs of individual
chromatids
3. Mommy version or
Daddy version of the
chromosome is
pulled to the pole of
the cell
4. No nuclear
membrane!!!!!!
ANAPHASE
1. Chromatids move to
the poles of cell
2. Spindle fibres hauled
in by the centrioles
3. Equal distribution of
DNA is the objective
Telophase
1. Chromosomes reach
the poles
2. Furrow appears
between cells about
to divide
3. Cytoplasm is equally
distributed to the
daughter cells
4. Mitochondria also
distributed
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The process of
division
The appearance of
two separate
daughter cells
follows shortly after
the completion of
this mitotic process.
Onion Root Tips – a blazing area of
Mitosis Activity
Summary
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The cell cycle is the life span of the cell.
Interphase is the first step in the cell cycle. Normal
cell growth and DNA replication occur during
interphase.
Prophase is the beginning of mitosis. The replicated
chromosomes become visible in this phase. The
nuclear membrane disappears
Metaphase follows prophase and is the stage in
which the lining up of sister chromatids occurs at the
metaphase plate.
Summary Cont.
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Anaphase is the stage of mitosis in which
the chromosomes begin moving to the poles
of the cell.
Telophase marks the end of the mitotic
process.
The two new daughter cells will now enter
Interphase and begin the cell cycle over
again.
Need to See it all Again?
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You want to know this
Quiz quiz quiz quiz
Hint, hint, hint, hint
Know all the phases
You have been … informed ….