Download The Cancer Poster

The Cell Cycle
NOTES
Today’s agenda:
 Review cancer
 Review Mitosis
 DNA worksheet
 Work from book:
 page 165 = Homework (or finish in class)
The Cell Cycle
The cell cycle is broken into three main components:
 Interphase
 Mitosis
 Cytokinesis
Interphase
 The longest portion of the cell cycle. During this phase, the
cell increases in size and makes the proteins necessary for the
cell to function. Some organelles start to duplicate.
Replication
 Towards the end of Interphase, some organelles start to duplicate,
and the DNA begins to uncoil or unzip itself to make a duplicate
copy of DNA.
End of Interphase
 The cell continues to grow.
 Chromatin is still in its loosely coiled form.
 Mitochondrias duplicate.
Activity –
DNA sheet
Mitosis
First things first…
 A few groups are still missing presentations.
 Presentations will resume today (lunch) and tomorrow.
 Microscope booklet – Due last week
 Cell lab sheet – Due last week (extras in the bin)
Today:
 Review Mitosis
 Introduction to asexual reproduction
Mitosis
 I – PMAT --What does that stand for?
 Interphase
 Prophase
 Metaphase
 Anaphase
 Telophase
The Beginning – Interphase
Well, more like this…
Original Cell
End of Interphase
Still looks like this…
Cell with Replicated Chromosome
and Organelles
What is Mitosis?
Mitosis is the process by which a parent cell divides into two
identical daughter cells.
Sometimes, there are errors during this process which will
result in genetic anomalies.
During this process, replicated chromosomes (which are
actually two chromatids held together by a centromere) are
separated and divided into two Daughter Cells.
Prophase
Two centrioles
nuclear wall
nucleolus
Early Prophase:
• Replicated Chromosomes coil up
• Nucleolus disappears
•Nuclear membrane begins to break down
•Centrioles are moving towards poles
•______________ fibers?
Late Prophase:
• Spindle fibers complete
•Chromosomes attach to spindle fibers
at their ______________________
•Nuclear membrane disappears
Metaphase
Spindle Fibers
centromere
• Tugging action of spindle fibers pulls X-shaped
chromosomes into a single line across the middle of
the cell.
Anaphase
• Spindle fibers contract
• Chromosomes split at centromeres
• Sister chromatids are pulled to opposite
sides of cell
Telophase
• A complete set of chromosomes is on
each side of the cell
• Spindle fibers disappear
• Nuclear membrane forms
• Nucleolus reappears
• One cell, two nuclei = the cell is ready to
divide!
Cytokinesis
What are these called?
Daughter Cells – Identical to parent cell
 Cell pinching: the swollen cell begins to pinch at the
equator, separating the cytoplasm and its contents
into two new cells.
Show what you know worksheet
Asexual Reproduction
Asexual reproduction: Only one parent is required, and the
offspring is a genetic copy to the parent, or a clone. Bread mould,
for instance, is a group of cloned cells from a single mould spore.
A new duplicate tree growing up from the bottom of another tree
is also a clone.
How about animals?
Cloning Animals –
Mimi
http://learn.genetics.utah.edu/content/cloning/clickandclone/
Cloning Worksheet – Work in pairs