Mitosis- means 2- (2 exact
cells with same nuclei
information)
Same amount of DNA/
Chromosomes are copies etc…
Mitosis is the type of cell
division that deals with body
cells (somatic cells) Ex; Skin
cells, muscle, hair etc..
5 steps/phases- to this type of
cell division known as Mitosis:
1- Prophase- the first TRUE
stage
2. Metaphase- looks like a
football
3. Anaphase
4. Telophase
(Cytokensis)
5. ? Interphase- “Getting ready
stage”
“The Pro Met Ana at the
telephone during
intermission.”
Prophase: The chromosomes
are pairing up and they are
finding their match. A nuclear
membrane is starting to
disappear, the chromosomes.
join together forming a knot
called a centromere. ( think
center)
Metaphase- (think of “m” for
middle) Looks to me like a
football- The chromosomes
line up in the middle of the cell
and they are still attached but
they are attached on a spindle
fiber which is connected to
poles.
3rd stage- Anaphase- (Think of
the visual of a magnet and it is
pulling the chromosomes apart
to opposite ends) The
chromosomes are separating
and drifting towards the
opposite ends (poles).Drifting
stage.. chromosomes are
moving to opposite poles! NO
LONGER ATTACHED!
4th phase- Telophase- (Think of
an old fashioned telephone) At
this stage the chromosomes
are separated they are at their
poles (opposite ends) and now
the cytoplasm is dividing into.
CYTOKINESIS ( cytoplasm)
*** During cytokinesis the
plant cell forms a CELL PLATE
(a line) which will form a cell
wall eventually.
Animal cells their cytoplasm in
cytokinesis pinches in forming
a “furrow” (an indention)
Interphase- Getting ready
stage- kind of like we make
copies and get ready for the
day) So in Mitosis the
chromosomes are copying
(replicating/ duplicating and
getting ready for Mitosis to
begin) The nuclear membrane
is visible.. but a lot is going on.
Chromatid- chromosomes that
are thickened, short, and are
duplicated.
Chromatin- Chromosomesthin and single in form.
SO IN THE END- MITOSIS
FORMS 2 NEW NUCLEI/ CELLS
WITH THE SAME GENETIC
INFORMATION. MITOSIS
FORMS BODY CELLS!!!
Meiosis- This is the type of cell
division that forms sex cells
also known as properly
“GAMETES” think they gotta
meet! So what meets:
egg + sperm= fertilization
a fertilized egg is known as a
zygote
*** Same phases or stages BUT
it has a PHASE 2:
Prophase 1, Metaphase 1,
Anaphase 1- etc….
Then it begins again:
Prophase 2…etc…
So the end RESULT is 4 SEX
CELLS or gametes…
These sex cells ( sperm and
egg) only carry ½ of your
parents genetic info.
Egg ( ½) of moms genetic info +
sperm ( ½) of dad’s genetic
information= a fertilized egg
which is the set amount of
chromosomes. Humans have
46.
Haploid is when it means ½ the
number this occurs in the egg
and sperm or sex cells. ***
THEN SEX CELLS ARE HAPLOID
IN NUMBER!!! Mitosis is
diploid in number:
Diploid is the doubled number
the END product (zygote)
Ex: 23 + 23= 46
Haploid are the 23 +23 ( egg +
sperm) = diploid number is 46
(fertilized egg)
Meiosis- Cell Division that
makes sex cells. Gametes are
the proper name for sex cells
(sperm and egg), 4 sex cells are
the end product for this type
of cell division, has a 2nd phase
to this type of cell division. The
sex cells are haploid in number
( means ½).