Download Cell Growth and Reproduction

Some Questions
• What makes us different from each other?
• Why are men typically taller than women?
• Why do dogs and cats have tails while humans do
not?
• The differences are caused by the differences in
DNA.
MUTATIONS & CANCER
DNA, Mutations and Cancer
• In Mitosis the original cell divides to make 2 identical cells
• What if the DNA in the original cell is exposed to radiation,
viruses or some type of chemical?
• The information in the DNA may be changed. These changes
are referred to as mutations.
• Some mutations may be good but most are not.
DNA, Mutations and Cancer
• The most common type of mutation known to humans is cancer.
• Cancer can be described as “cell division out of control”.
• Animation: How Cancer Grows
Cancer - some causes
• All cancers are caused by mutations in the DNA.
• Anything that causes mutations is called a carcinogen.
• There are three known types of carcinogens:
1.viruses ---------------> leukemia (white blood cells)
2. radiation ------------> skin cancer
3. hazardous material--> lung cancer
Cancer in Young People
• Usually cancer is thought of as an adult disease.
• Makes sense= more time passes=more opportunities
for mutations to occur
• Not always the case as young people get serious and
deadly forms of cancer as well.
Breast Cancer in Teenage girls
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Breast cancer in women ages 19-25 is on the rise
Why?
Habit of carrying a cell phone inside the bra.
Cell phone is directly against skin.
What carcinogen are people being exposed to from
this habit?
• Radiation!
News Clip
How are Cancer Cells Different from
Normal Cells?
• Normal cells cannot divide when isolated from one
another.
• Cancer cells can divide in isolation. This type of
growth can crowd and damage other cells.
• Cancer cells do not change shape and specialize as they
mature.
• This means they can’t do the same job as normal cells, they
are very inefficient.
• They use up the energy and resources of the other cells to
reproduce, but they do not do any work
Tumors
• Rapid cell growth (cancer) can result in a mass of
cells called a tumor.
• Tumors are classified as either benign or malignant.
• Benign tumors are harmless. They remain in one
area, causing little or no damage.
• Malignant tumors are dangerous because they can
spread
Review time
• Check your XP to see which abilities you have
earned.
• Review mitosis, DNA and base pairing rules for our
quiz tomorrow.