Cancer – A Mistake in the Cell Cycle Get out spirals Turn to page 46 Title Page and Update TOC Write critical question What are major differences between cancer cells and normal cells? With your shoulder partner talk about what happens during a normal cell cycle. Print 52-67

Is there any way to know who will develop cancer and when? U.S. Statistics The American public is presented with statistics about various characteristics of the U.S. and world populations. Scientists and healthcare professionals across many years has increased the gap between the number of people who develop cancer and the number of people who die from it. Is there any way to know who will develop cancer and when? 2, 3, 5, or 6 to stand - 4 in 6 of the people in the room will have children 3 stand – 2 out of 6 will be involved in an alcohol related accident 2 – will be diagnosed with cancer if 10 students are standing, ask 2 or 3 to sit – will die of cancer Stand if you know of or have a friend or family member that was diagnosed with cancer

What does a normal cell cycle look like? On your white boards: List what happens during each stage of the cell cycle? Your cells have checkpoints signaling when to divide and when to stop dividing. Cell growth, DNA Replication, more cell growth, organelles divide into two new cells, cytoplasm and cell membrane splits, two new cells are formed.

4 Factors that regulate the cell cycle and assure a cell divides correctly. DNA is checked to make sure it has replicated correctly. * A mistake in DNA replicated is a mutation* (If DNA does not copy itself correctly, a gene mutation occurs. DNA replication animation:click on DNA picture

2. Chemical Signals tell a cell when to start and stop dividing. (Target cells animation: click on go sign)

3. The amount of Space, signals a cell to divide or stop dividing. If space is available the cell divides. When cells run out of space, they stop dividing (Normal contact inhibition animation: click on petri dish)

4. Apoptosis occurs. Apoptosis is programmed cell death If a cell is damaged or does not function properly it will kill itself so further mutated cells are not produced. (Target cells animation: click on go sign)

Cancer is a disease of the cell cycle. Some body’s cells ignore the normal checkpoints and the cells continuously divide, forming tumors.

So what causes cancer cells to ignore the cell cycle’s signals?

Mutations cause a disruption in the cell cycle. Mutations may be caused by: 1. radiation (UV rays) 2. smoking 4. chemicals - cleaning 3. Pollutants 5. viruses 6. genetic

While normal cells will stop dividing if there is a mutation in the DNA, cancer cells will continue to divide with mutation.

The 4 Stages of Cancer . Stage Description I cancer cells are small and have not invaded surrounding tissue II tumour is larger than in stage 1. III Cancer is larger than stage 2 and has invaded surround tissue in the organ it started in IV The cancer has spread from where it started to another body organ. This is also called secondary or metastatic cancer.

On your white board complete the right side to the list – shoulder partner Normal Cell Division DNA is replicated properly. 2. Chemical signals start and stop the cell cycle. 3. Cells communicate with each other so they don’t become overcrowded. 4. Cells perform apoptosis if they do not function properly Cancer Cells Mutations occur in the DNA when it is replicated. Chemical signals that start / stop cell cycle are ignored. Cells do not communicate with each other and tumors form. Cells do not perform apoptosis and continue to divide

Answer the Critical Question What are major differences between cancer cells and normal cells?

Close your eyes… Stand if you know of or have a friend or family member that was diagnosed with cancer Faces of Cancer Activity- You will learn more about who develops cancer, when, and why, by assuming the identities of 1 of the 30 case files.

Sharing the Class’ Data

Complete the Discussion Questions Each group will be assigned a random question to present to the class.

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