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.
chromatin
duplicatedchromosome
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/outreach/bioclips/CDBio.html