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It’s The
circle of cell
life
How do cells reproduce and
grow?
Why do cells
divide?
To replace other cells that have been
damaged or worn out
To allow multicellular organisms to grow
For asexual reproduction
Because they get too big!
What is MITOSIS?
Mitosis is the process by which the
nucleus of one cell DIVIDES into two
nuclei
Therefore, each cell has the same genetic
material as the original cell
Its like “photocopying” the cell- the two
daughter cells are identical
Genetic
Information
 Genetic information is contained in the DNA of
the cell
 DNA is found in the thread-like coils called
CHROMATIN when the cell is NOT dividing
 When the cell is dividing, the chromatin
condenses (packs into) chromosomes
 genes are small sections of chromosomes that
contain the information for a specific cell
function
The big
picture
Human
Chromosomes
The cell cycle
Cell Cycle
The cell
spends the
most amount of
time in
interphasegrowing
Cell CycleInterphase
 During INTERPHASE
the cell is GROWING
and preparing to
reproduce
 The cell’s DNA is being
copied (replicated)
 The DNA is in the form
of loosely coiled
CHROMATIN
Cell CycleMitosis
Remember! Mitosis is the stages of the cell
cycle in which the nucleus and cell divides
Mitosis is divided into:
Prophase
Metaphase
Anaphase
Telophase
Cytokenesis
Cell Cycle
The cell
spends a very
short amount
of time in
mitosisdividing
The phases
of mitosis
Early Prophase
 Chromosomes are
condensed and
consist of 2 sister
chromatids
 The nuclear
membrane begins to
break down
 Spindle fibers appear
Late Prophase
 The CENTROMERE
joins each pair of
sister chromatids to
the spindle fiber
Metaphase
 Chromosomes line up
along the middle of
the cell
Anaphase
 Spindle fibers
separate sister
chromatids and pull
them apart
 Once they have
separated they are
individual
chromosomes
Telophase
 Spindle fibers
disassemble
 Nuclear envelope
reforms
 The nuclear envelope
will become the
nuclear membrane
Cytokinesis
 In animal cells, cell membrane pinches off
forming two new separate cells
 In plant cells, cell membrane pinches off and
a cell wall forms
 The cytoplasm is divided between the two
cells
Mitosis in
action!
How am I
going to
remember this?
Think IPMATC!
Phase name
I
P
M
A
T
C
mnemonic