Transcript The Cell Cycle

The Cell Cycle
WELCOME TO MY MAGIC SHOW!
First, I am going to make a
very small ball turn into a
larger ball.
Then, I am going to make
the larger ball split into
two smaller identical balls.
(Oooooh, aaaaah!!!)
Interphase
• The stage that the cell spends
most of it’s life in.
• Consists of 3 phases:
•G1 phase
•S phase
•G2 phase
G1 phase
• Point in a cell’s life where it
does most of it’s growing.
• The cell increases in size
because of protein, DNA and
organelle synthesis.
S Phase
•Stage of cell life in which
chromosomes are
replicated.
•DNA is copied during
DNA replication.
duplicated
chromosome
chromatin
G2 phase
•This is the preparation
phase for mitosis.
•Organelles and proteins
needed for mitosis are
synthesized.
Overview of Interphase
• The cell is synthesizing the
materials that are vital for
growth, development, and cell
division (mitosis).
• DNA is copied.
• mRNA, proteins and organelles
are made.
• The cell is increasing in size
and preparing to divide.
Mitosis
• The “BIG SHOW”!
• Occurs in body cells.
• Is needed when the cell
becomes too large due to the
growth that occurs during
interphase.
• Consists of 4 phases.
4 Phases of mitosis:
•Prophase
•Metaphase
•Anaphase
•Telophase
Now for my next trick I
will make not 1, but 2
things disappear and 2
things appear!
Prophase
• The chromatin condenses to
form chromosomes.
• Centrioles separate and
spindle fibers start to form.
• The nucleolus and nuclear
membrane disappear.
What did the talented and
impressive magician make
appear? Disappear?
Magic trick
Appear
1. Chromosomes
2.
Spindle
fibers
Disappear
1. Nucleolus
2. Nuclear
membrane
Metaphase
• The chromosomes line up in
the MIDDLE of the cell .
• M is for Meta-, M is for Middle
• Mitotic spindle fibers connect
the centromeres to the
centrioles.
Anaphase
• The sister chromatids
separate becoming individual
chromosomes.
• The chromosomes move to
opposite poles of the cell.
• A is for Ana-, A is for APART!
Telophase
•The chromosomes and
spindle fibers disappear.
•The nuclear membrane and
nucleolus re-appear.
•The two new cells are
almost completely formed.
telophase
• Telophase is the reverse of
prophase!
• The two things the magician
made disappear he now makes
re-appear!
• The two things the magician
made appear magically
disappear!
Cytokinesis
•The division of cytoplasm
(cytokinesis) is now
complete and we have two
new identical cells.
•We call these cells
daughter cells!
So did you like the
show?
Is this
individual
male or
female?
Stages of mitosis in onion root tip cells
Cell Division Animation
• http://www.loci.wisc.edu/outrea
ch/bioclips/CDBio.html