Unit 1 Section 6: Mutations and Cancer

Cancer: uncontrolled division of cells. link to an Internet Website

click to find the answer to today's question Can cancer be inherited?

Electron Microscope

There are over 200 different kinds of cells in the human body. These cells are continually dividing, under the control of the genes within each cell. The length of time between cell divisions differs widely from one type of cell to another. Some cells in the intestine divide twice each day, while liver cells might divide only once every 18 months.

The DNA in cells code for the production of an estimated 100,000 different proteins in humans. Some of these proteins are responsible for the chemical signals that control growth and division of cells. If the code, or the proteins themselves are malformed, the result can be a cancer cell.link to an Internet Website

Anything that damages cells might cause cancer.

Over the course of your lifetime, the DNA of a single gene may be damaged several billion times. Therefore, a single "injury" is not the cause of cancer. Something much more significant must occur. About 20 human genes have been identified that, when altered, can lead to the more common types of cancer.

  Watch News flashes on Cancer link to an Internet Website
Carcinogenlink to an Internet Website an agent that leads to the production of a cancer cell. These include, but are not limited to, chemicals like formaldehyde and benzene, radiation, tobacco, and some viruses.

**Short video clip on carcinogens:

  1. What do regulator genes do?

  2. What genes control the creation of proteins?

  3. What type of genes lead to the formation of cancer?

  4. What are 3 examples of very active Carcinogens?

  5. If humans were to rid the environment of most of the carcinogens, by what percentage would cancer rates decrease?


Mutagenlink to an Internet Website a substance that causes mutations to occur in a cell.

Tumor - a mass of cells resulting from uncontrolled, abnormal cell division.

Types of tumors:

Leukemia - uncontrolled production of white blood cells.

click for a career
Treatments for cancer:

Surgery - physically removes the cancer cells from the body.
Chemotherapylink to an Internet Website chemicals taken internally to kill cancer cells.
Radiation therapy link to an Internet Website- exposing the tumor to radiation to kill cancer cells.
Hormone therapy link to an Internet Website- taking medications that interfere with hormones.
Biological therapy link to an Internet Website- uses the body's immune system to fight cancer.
Targeted therapy link to an Internet Website- drugs are used to block growth and spreading of cancer.
Gene therapy link to an Internet Website- introducing genetic material into DNA to fight cancer.


*Take a look at some other treatments for cancer: link to an Internet Website


Cancer facts and figures for 2007 from the American Cancer Society link to a local webpage


1.6 b Assignment - Mutations and Cancer
Scoring criterialink to a local webpage

  1. Over the course of your life time, how often is the DNA of a single gene damaged ? Are these the cause of cancer? Explain
  2. Summarize in your own words, how normal cells and cancer cells behave differently.
  3. Cancer cells go through different stages of development. What part is usually responsible in killing the organism/patient? (hint: see first link on this page)
  4. View the animation video's at this site: National Cancer Institute link to an Internet Website and complete the following questions.
    • What keeps the rate of cell division equal to the rate of cell death?
    • Describe a tumor.
    • What is the cell cycle clock?
    • What type of genes play a major roll in regulating the cell cycle?
    • What is the function of tumor suppressing genes?
    • How are the answers in the previous two questions related?
    • What important mile stone came in the 1970's about cancer?
    • How do mutations affect proto-oncogenes and tumor suppressing genes?

Honors biology: complete the above section along with this section.

  1. View the news flash link (top of page) on cancer and give a brief summary of each episode.

1.6 c Mutation & Cancer

click to find the answer to today's question Tobacco is not only a carcinogen, it is a teratogen.
What is a teratogen?

Table 2
Classification of Skin Types
Skin Type Hair Complexion Freckles Sun Reaction Tanning
I Red or Blond very fair +++ always burns never tans
II Blond fair ++ often burns tans lightly
III Blond or Light Brown fair to medium + to 0 sometimes burns tans progressively
IV Brown Olive 0 rarely burns tans easily
V Brown to Black dark 0 rarely burns tans deeply
VI Black very dark 0 never burns tans deeply

1.6 c Assignment - Mutations and Cancer
Scoring rubric
link to a local webpage  word doc. version link to a local webpage

  1. Did you know that Arizona has a high rate of skin cancer related to UV light?
  2. What do you know about skin cancer?
  3. How many people has it affected and how many people has it caused to die?
Many people are dying from skin cancer and based on information about skin cancer a proposed statute has been put forward that would require that young people protect themselves from UV radiation. View this video to get details about the proposed statute. link to an Internet Website What is your opinion on this situation? Would you support the statute, make changes to the statute or not support it at all. Read and follow the directions at this link link to a local webpage word doc. version link to a local webpage and get ready to support your point of view

***Be sure to print out scoring rubric linked above***


  Research Links:

Biology Class Evolution Page










Cancer cannot be inherited, but the tendency to develop cancer is hereditary.










A taratogen is something that can cause malformations of an embryo or fetus.
A developing human embryo is most vulnerable to these substances in its earliest stages - even before a woman knows she is pregnant.