Mitosis
Why do cells divide?
• The larger a cell gets, the more
demands it places on its DNA
• As a cell gets larger, it has more
trouble moving enough nutrients
(food) and waste across its cell
membrane
Before a cell
gets too large
it divides.
Cell division
is the process
by which a
cell divides
into two new
daughter
cells
Cell division
occurs in a
series of stages
or phases…..
Interphase
• Using Latin P&S, Interphase means –
Between phase
• Chromosomes are copied (number
doubles)
• At the beginning of this phase
chromosomes appear threadlike and
are known as chromatin, but by the end
of this phase chromosomes have taken
a new shape
Interphase
Prophase
• MITOSIS BEGINS
• Using Latin P&S, Prophase means –
Before phase
• Cell begins to divide
• Centrioles appear and begin to move to
opposite ends of the cell
• Spindle fibers form between the
centrioles
• Nuclear membrane begins to break down
Prophase
Metaphase
• Chromatids attach to
spindle fibers
• Chromatids are lined up in
the MIDDLE
Metaphase
Anaphase
• Chromatids separate
and begin to move to
opposite ends of the cell
Anaphase
Telophase
• Using Latin P&S, Telophase means –
End phase
• Two new nuclei form
• Chromosomes once again appear as
chromatin (threads rather than rods)
• MITOSIS ENDS
Telophase
Cytokinesis
• Cell membrane moves
inward to create two
daughter cells – each with
their own nucleus and
identical chromosomes
Cytokinesis