Section 8.3: Cancer and the Cell Cycle
Name __________________________
1. In what ways do enzymes control the cell cycle?
Cells monitor the progress from phase to phase. Some enzymes begin and drive the cell cycle while
others regulate one phase to another.
2.
What is cancer and how does it start? (discuss the role of enzymes in your answer)
Cancer is uncontrolled cell division because enzymes that regulate the cell cycle are not produced,
are overproduced, or produced at the wrong time. Cancer is uncontrolled mitosis!!!
3.
What is a gene? How does it relate to enzymes?
A gene is a segment of DNA that codes for the production of a protein (like an enzyme), these
enzymes then regulate the Cell Cycle. If the genes are damaged, then the enzymes might be
overproduced, not produced at all or are made at the wrong times.
4.
Describe the stages of cancer (begin with genes and end with metastasis)
1. There is a change in the genes that produce the enzymes that control the cell cycle
2. Enzymes are turned on at the wrong time, are overproduced, or not produced at all
3. The cells then keep dividing and form a tumor (mass of cells), that deprives normal cells of
nutrients and so the normal cells die.
4. Tumor continues to grow over time.
5. In later stages of cancer, the cancerous cells can enter the bloodstream and spread throughout
the body (this is called metastasis).
6. Metastasis will cause new tumors in other areas of the body (called cancer spreading)
5. What proof exists for the environmental cause of cancer?
Different people from different countries develop different types of cancer at different rates. (ex.
Breast cancer is high in US and low in Japan).
Also, when people move from one country to the next, cancer patterns follow the country where
they are now living rather than the country where they came from.
6. What happens to the patterns in cancer if a person moves to another country?
Also, when people move from one country to the next, cancer patterns follow the country where
they are now living rather than the country where they came from.
7.
What are some other environmental factors that can cause cancer? (5-6 total)
Cigarette Smoke, Air and Water Pollution, exposure to UV rays, viruses that damage genes, diets high in
fats.
8.
How can cancer be prevented? According to your book, what are three things that you can do to avoid
cancer?
 Living a healthy lifestyle by eating a diet low in fats and high in fiber
 By eating lots of fruits, vegetables, and natural grain products
 By taking vitamins and minerals or eating foods high in these
 Exercising Daily
 By NOT SMOKING!!!
9.
What are some treatment options? We will talk about these as a class, so leave blank.
o Some cancers can be treated or held at bay by changing dietary habits
o Chemotherapy where patient is injected with certain chemicals that target specific cells like
cancer cells and kill them. Major side effect, it also affects other cells in the process (why
some people lose hair).
o Radiation therapy – where patient is subjected to intense radiation to target and kill off
cancer cells
o Nuclear Medicine – where patients are given radioactive elements in nutrients or injected
to target cancer cells (cancer cells absorb all nutrients) and kill them.
10. What does metastasis mean?
When cancerous cells enter the bloodstream and cause tumors to develop in other areas of the
body; cancer spreading.
11. What is a carcinogen?
A carcinogen is a cancer causing agent; anything that causes cancer.
(Ex. Asbestos, UV rays, Smoking, etc.)
12. What are some examples of carcinogens?
Viruses, Smoking, UV rays, Air and Water Pollution, Asbestos, Mercury
13. What is a tumor and how is mitosis related to it?
A tumor is any uncontrolled growth of tissue, can be benign or malignant
Benign = not cancerous
Malignant = cancerous and dangerous
14. How are UV rays (a type of environmental factor) connected to cancer? Use the following words in
your response: (underline them) tumor, gene or DNA, mutation, enzyme, and cell cycle.
UV rays can a mutation in a DNA/gene or damage genes in skin cells causing enzymes that control
cell cycle to be affected. The enzymes do not work properly causing uncontrolled cell division
(cancer) and a tumor develops. Normal cell cycle is not occurring.