Download Cell division

 All
living organisms are made of cells.
 Cells
are the basic unit of structure and
function in all living things.
 Cells
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come from pre-existing cells.
Through both sexual and asexual reproduction.
• Look at the picture to the right.
• The green part of the potato will
grow into a second potato exactly
like the first one. It is BOTH parents.
• Asexual reproduction is
a type of reproduction in
which a new organism is
produced from only one
parent and has the same
DNA as the parent.
• In humans it happens in
most of our body cells.

Interphase – DNA is replicated (copied)
on each chromosome. This is the
longest phase of the cell cycle and
where the DNA “unzips” and makes two
strands (1/2 old and ½ new).

Mitosis - The big idea to remember is
that mitosis is the simple duplication
of a cell and all of its parts. It
duplicates its DNA and the two new
cells (daughter cells) have the same
pieces and genetic code. Two identical
copies come from one original.

Cytokinesis - the cell splits into 2 new
cells which are exact copies of each
other,
 Interphase-
The first stage of the cell cycle.
Interphase happens BEFORE cell division and
mitosis.
 Several things must occur first before the cell
can divide.

The most important thing is for the DNA to be copied or
replicated so that each cell has a copy of the original
DNA.
 The DNA is “unzipped” and base pairs match up to
create 2 exact strands from the original.
 Mitosis-
The stage of the cell cycle where the
cell’s nucleus actually divides into 2 new nuclei
resulting in an exact copy.
 Both cells now have the same genetic code.
 Two identical copies come from one original.
 Start with one cell and get two that are the
same.
 Mitosis is divided into four stages of its own.
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Prophase
Metaphase
Anaphase
Telophase
 This
is how most of our somatic (body) cells
are reproduced.
 Mitosis
allows us to grow and develop.
 Cells
have a limited lifespan. They
eventually can’t function and need to be
replaced.
 The
cell cycle with mitosis is the beginning
of the process by which the cells are
replaced with exact clones of the old cell.
Mitosis Video Clip
 Some
simple organisms reproduce this way.
 Cancer
and other diseases can happen
when a mistake (mutation) is made in
mitosis.
 For
reasons that scientists are still trying to
figure out, this mutated cell or group cells
begins to replicate themselves very
quickly.
 These
abnormal cells then can spread to
other parts of the body.
Cancer Cell vs Normal Cell Growth
 Cytokinesis
- the last stage of the cell division
cycle. This happens AFTER mitosis and the second
nucleus is completely formed.
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The animal cell membrane pinches in around the middle
of the cell.
A new cell wall is created in a plant cell.
The plant or animal cell splits into two daughter cells.
Each daughter cell ends up with an identical set of
chromosomes.
 At
the end of cytokinesis, each new cell enters
interphase and the cycle starts over to make more
cells. Asexual reproduction is a never ending cycle
in your body.
The whole cycle of somatic cell division typically lasts from 8 to 24
hours in humans.
A
type of reproduction in which a new organism
is produced from one parent and has the same
DNA or genetic material as the parent. This is
also how somatic (body) cells are reproduced.
 Making an exact copy of a cell.

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To allow growth and development
To replace old cells
To repair damaged cells
To create new organisms
Brain Pop Asexual Reproduction
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Mitosis
Cloning
Budding
Animal Regeneration