Cancer -

Cells division is …
• The multiplying of cells through mitosis
resulting in generation after generation of
identical daughter cells. The daughter cells
receive exact copies of the parent cell’s
Why do we need cell division?
1. Allows us to grow
2. Allows us to heal and repair ourselves
3. Even allows us to reproduce
The Reasons for Cancer
• Cancer occurs when:
– the rate of cell division goes out of control.
– Mutations occur in the genes that control cell
• Mutations are cells with changes to their
• A Carcinogen is any chemical or energy
that causes a mutation in DNA.
The Reasons for Cancer
• Cancer cells reproduce in defiance of the
normal restraints:
‒ They don’t stop at
the checkpoints in
the cell cycle
‒ They lack cell-to-cell
‒ They resist to cell
“suicide” signals
Images of Cancer
• The following slides include images of
advanced stages of different cancers.
• The images may be somewhat disturbing,
so if you are squeamish, you may want to
cover your eyes.
Skin Cancer
Lung Cancer
Brain Cancer
Oral Cancer
Tumor on Spleen
Causes for Cancerous Mutations
1. Viruses
- some viruses interfere with cell
division by inserting their own DNA
2. Radiation
- high energy radiation like ultraviolet
light, X-rays and Gamma rays have
been linked to forms of cancer
3. Chemicals
- cigarette smoke and smog have been
linked to lung cancer
Tumour Terms
A tumour is a mass of disfunctional cells
that have a grown from mutant parents.
1. Benign tumours: mainly harmless
Cells remain clustered together.
2. Malignant tumours: can be deadly.
– Parts of these tumors can break off and
spread throughout your body (metastasis).
Cancer Treatments
1. Surgery: tumour is
cut out.
2. Radiation Therapy:
radiation is used to kill
the tumour cells
3. Chemo Therapy:
Toxic chemicals
attempt to poison the
cancer cells (stop
Or a combination of all 3.
Reflect On Your Learning
• Produce a K-Q-L chart for this lesson in
your notes.
Identify 2-3
things from
the lesson
that you
already knew
Identify 2-3
that you now
have about
the lesson
Identify 2-3
things that
you learned
about during
the lesson