Transcript Mitosis - Education Service Center, Region 2

Mitosis
 What
is it?
 Why is it
Important?
 What
do I
need to
know?
Where did this plant and animal
come from?
Where did these cells come from?
Why do cells divide?
Cell division happens in all
organisms.
• reproduction
• growth or repair
Why do cells divide?
Important fact
In unicellular organisms, cell division
is important for reproduction. To
create another organism, they just
divide into two.
Why do cells divide?
Important fact
In multicellular organisms, cells
divide to allow the organisms to
grow, repair or replace cells.
vocabulary
word!
cell cycle – the life cycle of a
eukaryotic cell.
Cells have a life span. They live and
die like any living thing.
To grow and remain healthy, cells
need to divide and replace
themselves frequently.
The Cell Cycle
Important fact
The cell cycle has three phases:
• interphase
• mitosis
• cytokinesis
interphase
vocabulary
word!
interphase – part of the cell cycle
when it is not dividing. This is when
the cell is performing its job for the
organism. At the end of interphase,
DNA makes a copy of itself.
Important fact
A cell spends 95%
of it’s life cycle in
interphase.
DNA
Important fact
DNA is a molecule that determines
the traits of a living organism. It
makes us who we are.
DNA replication
Important fact
During interphase, right before
mitosis, the DNA makes an exact
copy of itself.
Chromosomes duplicate
mitosis
vocabulary
word!
mitosis – part of the cell cycle when
the nucleus divides.
Important fact
At the end of mitosis, there are two
identical nuclei in the cell.
mitosis
Important fact
There are four phases in mitosis:
• prophase
• metaphase
• anaphase
• telophase
prophase
vocabulary
word!
prophase - during
prophase, the
chromatin in the
nucleus condenses
into chromosomes.
The membrane
around the nucleus
breaks down.
PROPHASE
Allium root tip
Coregonus blastula
metaphase
vocabulary
word!
metaphase - during
metaphase, the
chromosomes line
up in the middle of
the cell.
Spindle fibers form
METAPHASE
Allium root tip
Coregonus blastula
anaphase
vocabulary
word!
anaphase - during
anaphase, the
chromosomes
separate. They are
pulled to opposite
sides of the cell so
each side has an
identical copy.
ANAPHASE
Allium root tip
Coregonus blastula
telophase
vocabulary
word!
telophase - during
telophase, a new
nuclear membrane
forms around each
group of
chromosomes.
TELOPHASE
Allium root tip
Coregonus blastula
cytokinesis
vocabulary
word!
cytokinesis – the division of the
cytoplasm and cell organelles.
INTERPHASE
Allium root tip
Coregonus blastula
http://vimeo.com/8333643
Mitosis produces identical
offspring (2N---2N)
Name stage of mitosis

prophase
Name stage of mitosis
Name stage of mitosis
Name stage of mitosis
Name stage of mitosis
Name stage of mitosis
Name stage of mitosis
Name stage of mitosis
Mitosis
Cells Alive demo
http://www.cellsalive.com/mitosis.htm
 http://www.neok12.com/CellDivision.htm
