Cancer and Stem Cells Quiz Review

1. What is cancer?

Cancer is when cells grow and divide uncontrollably. They don’t stop like normal cells do.

2. In which types of cells is cancer more likely to develop? (Hint: What types of normal cells divide rapidly?)

In places where cells divide a lot, like:

• Skin

• Intestinal (gut) lining

• Blood

These cells are always replacing themselves, so they have more chances for mistakes (mutations).

3. Explain the difference between a mutagen and a carcinogen.

• A mutagen is anything that changes DNA.

• A carcinogen is a mutagen that causes cancer by affecting how cells divide.

4. Label the diagram to the right with the following terms: benign tumour, malignant tumour, metastatic cell, normal cell, normal cell division, uncontrolled cell division.

• Normal cell – healthy, works properly

• Normal cell division – cells divide when needed

• Uncontrolled cell division – cells keep dividing when they shouldn’t

• Benign tumour – not cancerous, doesn’t spread

• Malignant tumour – cancerous, can spread

• Metastatic cell – cancer cell that travels to another part of the body

5. List 4 known carcinogens.

• Cigarette smoke

• Viruses (like HPV)

• Radiation (like X-rays or UV light)

• Certain chemicals (like solvents,organic, or pollution)

6. Why do the chances of developing cancer increase as a person gets older?

The older you get, the more time your cells have had to get DNA damage. More damage = higher chance of cancer.

7. Describe four steps for metastasis, the formation of a secondary tumour.

1. A tumour forms from cells that divide too fast.

2. The tumour grows its own blood supply.

3. Some cancer cells break off and enter the blood or lymph.

4. These cells travel and form new tumours in other places (called secondary tumours).

8. List 2 lifestyle choices or actions that can reduce your chances of developing cancer.

• Stay active and exercise regularly.

• Eat healthy foods — lots of fruits and vegetables.

(Also: avoid smoking and protect your skin from too much sun.)

9. How is cancer diagnosed, once a tumour has been located?

A biopsy is done — a small sample of the tumour is taken.

Doctors look at it under a microscope to see if there are too many cells dividing.

10. What are 3 main methods of treating cancer?

• Surgery – remove the tumour

• Radiation – kill cancer cells with high-energy rays

• Chemotherapy – use drugs to stop cancer cells from dividing

11. What are some reasons why cancer might recur after it has been successfully removed from a person?

Some cancer cells might survive surgery, chemo, or radiation. They can grow again later.

12. Most chemotherapy drugs are chemicals that inhibit DNA replication. Explain how these drugs would stop cancer cells, using your knowledge of the disease and of cell division.

Chemo drugs stop DNA from copying. Without copying DNA, cancer cells can’t divide and grow.

13. For the following types of stem cells, complete the table using the phrases provided: found in embryo, mostly blood cells, umbilical cord and placenta, brain, bone marrow and other organs, cells found in that organ, all cells of the body.

Type Where Found What They Can Become

Embryonic In embryos Any cell in the body

Adult Brain, bone marrow, organs Only certain cells from that area

Umbilical Umbilical cord or placenta Mostly blood cells

14. What is the main difference between adult stem cells and embryonic stem cells?

• Adult stem cells can only become a few specific types of cells.

• Embryonic stem cells can become any kind of cell in the body.

15. List four diseases that stem cell transplantation technologies may help to alleviate.

• Cancer

• Alzheimer’s

• Parkinson’s

• Diabetes

(Also: spinal cord injuries)

16. Why might an organ grown from your own stem cells be better suited to you for an organ transplant rather than one donated by another person?

Because they’re made from your own cells, your immune system won’t attack or reject them.