Cell reproduction
• Cell theory states that all
cells come from preexisting
cells.
• Cell division is the process
by which new cells are
produced from one cell.
• Results in two cells that are
identical to the original.
Chromosomes
• Carriers of genetic material
that is copied and passed
from generation to
generation of cells.
• Exist as chromatin for most
of the cells life.
Chromatin
• Long strands of DNA wrapped
around proteins.
• As the nucleus begins to divide,
the chromatin becomes tightly
packed.
Cell Cycle
• The sequence of growth and
division of a cell. (Interphase,
Mitosis, Cytokinesis)
• The majority of a cell’s life is
spent in the growth period
known as Interphase.
Interphase
1. Majority of a cell’s life is spent in this
growth period.
2. Cell growth and protein production is
high.
3. Cell copies its chromosomes
4. Cell parts needed for cell division are
assembled.
G1 phase
• First phase of interphase
• Chromosomes not visible cause
they are uncoiled
• Protein synthesis is occurring as
the cell grows and develops
S stage
• Chromosomes are replicated
• Chromosomes divide to form
identical sister chromatids
connected by a centromere
G2 phase
• Chromosomes begin to shorten
and coil
• Protein synthesis in high gear
• Centriole pair replicates and
prepares to form the mitotic
spindle
Mitosis
• Process by which two
daughter cells are formed,
each containing a complete
set of chromosomes
identical to the parent cell.
• Consists of 4 phases
Mitosis
• Prophase (first and longest
phase)
• Metaphase
• Anaphase
• Telophase
Prophase
• Chromosome copies are held
together at their centers, so they
form a sort of “x”
• Nuclear membrane and nucleolus
disintegrate.
Metaphase
• The two copies of each
chromosome line up in the
center of the cell
Anaphase
* One complete set of
chromosomes is pulled to one
side of the cell.
* The other complete set is
pulled to the other side of the
cell.
Telophase
• Chromosomes unwind
• Spindle begins to breakdown
• New nucleus and nuclear
membrane forms around each
set of chromosomes.
Division of cytoplasm
(Cytokinesis)
• Plasma membrane pinches
in along the equator
• Two new cells are
separated
Its mitosis time karaoke
Results of mitosis
• Process that guarantees genetic
continuity, resulting in the production of 2
new cells with chromosome sets that are
identical to those of the parent cell.
• These new daughter cells will carry out the
same cellular processes and functions as
those of the parent cell and will grow and
divide just as the parent cell did.
Stem cell research
• http://ec.europa.eu/commission_barroso/p
otocnik/funscience/funscience_en.htm
• http://www.films.com/id/12968/Fetal_Fix_S
tem_Cell_Research_and_Moral_Conflict.h
tml
• http://www.kqed.org/quest/television/view/
326?gclid=CMnjwoT9hJACFShbiAodTnCJ
oA