Wednesday, November 30th Miss Brawley

Do Now: Have your workbooks ready on your desk for a notebook check. Turn in your Lesson 2 Quiz to the bin. Answer the Chapter Mystery on Page 287

When Cells Go Rogue

Cells Gone Rogue Special Agent Training Camp (cell cycle) produces new agents But what happens when Training Camp becomes a breeding ground for Rogue Agents?!?

Cancer: Uncontrolled Cell Growth Cancer cells don’t respond to normal regulatory signals. Cell cycle is disrupted. Cells grow and divide uncontrollably. tumor Ask students to share what they already know about what cancer is. Encourage them to relate what they already know to what they have been learning about the cell cycle. Explain that cancer is a disease of the cell cycle. Ask a volunteer to point to the area in the diagram that shows cancer. Click to reveal the label for the tumor. Tell students: Cancer cells form a mass called a tumor. Ask: How do you think a tumor like this formed? Answer: One cell started dividing too fast; there was no control over the cell cycle. Click to reveal the bullet points, reading each one in turn. Ask students why they think a rapidly growing mass of cells can be harmful to healthy cells. Guide students to realize that cells need resources to grow and divide. When cancer cells grow uncontrollably, they not only displace healthy cells and tissues by taking up space but they also use up resources that normal cells need. blood vessel

Cancer Formation: A Closer Look A cell begins to divide abnormally. Cells produce a tumor and start to displace normal cells and tissues. Cancer cells move to other parts of the body. Ask for student volunteers to “narrate” what the images are showing about the development of cancer. Click to reveal each step in turn as volunteers correctly describe the step. Elaborate on step 3 to explain that cancer is so dangerous because these abnormal cells can break free from their original site and move to other parts of the body through the bloodstream or lymphatic system, where the cells can continue to grow and divide out of control. The formation of secondary tumors is called metastasis. Ask: What makes cancer cells different from healthy cells? Answer: Cancer cells do not respond to the signals that regulate cell growth and division. They continue to divide when healthy cells would stop. Ask: When researchers develop drugs to fight cancer, what characteristics of cancer cells do you think they target? Sample answer: They might target rapidly developing cells. Misconception alert: Explain that while we use the term “tumor” to refer to a clump of cancer cells, not all tumors are truly cancerous. A benign, or noncancerous, tumor does not spread to surrounding healthy tissue. A malignant, or cancerous, tumor invades and destroys surrounding healthy tissue.

Pearson Realize Abnormal Cell Division Cell Growth

What Causes Cancer? In all cancers, control over has broken down. Cancer results from a defect in genes that control cell growth and division. the cell cycle Ask a volunteer to come to the board and write in the missing terms or to verbally identify what correctly fills in the blank. Click to reveal the correct answer. Ask students to share some of the things they have heard in the news about what causes cancer. Answers may vary, but many students will offer ideas such as smoking, tanning, and exposure to X-rays. Click to reveal the text. Point out that there are, in fact, many triggers for cancer, but that all of these ultimately disrupt the genes that regulate cell growth and division. The result of the gene defects is that some cancer cells no longer respond to external regulators and others no longer produce internal regulators. Defects in these genes may be caused by tobacco use, radiation exposure, other defective genes, and even viral infections.

Cancer make me lose control Cancer cells do not heed the normal signals which shut down the cell division process; they continue to divide when they are very densely packed and/or if the protein(s) that regulate cell division are not functioning properly due to a mutation.

Cancer make me lose control Cancer begins when a single cell is transformed into a cancer cell, one that does not heed the regulation mechanism. Normally the body’s immune system will recognize that the cell is damaged and destroy it, but if it evades destruction, it will continue to divide by mitosis and each daughter cell will be a cancer cell.

Cancer make me lose control A mass of these cells that invades and impairs the functions of one or more organs is called a malignant tumor. A benign tumor is a mass of abnormal cells that remains at the original site.

Cancer make me lose control Cancer cells may also separate from the original tumor, enter the blood and lymph vessels of the circulatory system, and invade other parts of the body, where they grow to form new tumors. *T, N, M: Tumor (localized)  Nodes (lymph/blood)  Metastasis (spreads)

Treatments for Cancer Surgery to remove localized tumor Radiation to destroy cancer cell DNA Chemotherapy to kill cancer cells or slow their growth Explain that for a tumor that has not spread, surgery can often be sufficient to remove the cancer. This treatment is common for skin cancer. Radiation is used to destroy the DNA of cancer cells, which must divide quickly and therefore must duplicate their DNA rapidly. In chemotherapy, chemicals targets cells as they are dividing. Ask: What unintended effects might radiation and chemotherapy have? Answer: They could also disrupt healthy cells that are dividing. Point out that unintended consequences of cancer treatments are motivating researchers to learn even more about the proteins that control the cell cycle so they can find more specific ways to target cancer cells without harming healthy cells.

Class Work Workbook 10.3: Pages 150-152 Read Pages 292-297 Textbook

Homework: Lesson 3 Quiz