Cancer+questions+hw-+kat

Define: apoptosis, telomeres, metastisis, tumor, proto-oncogenes, oncogenes, growth factor, tumor suppressor gene, oncology, carcinoma, sarcoma, leukemia, lymphoma
 * Apoptosis**: when a cell dies
 * Telomeres**: tip end of a chromosome
 * Metastasis**: spread of cancer from the place of origin throughout the body; caused by the ability of cancer cells to migrate and invade tissues.
 * Tumor**: cells derived from a single mutated cell that has been repeatedly undergone cell division
 * Proto-oncogenes**: normal gene that can become an oncogene through mutation
 * Oncogenes**: cancer causing gene
 * Growth factor**: chemical signal that regulates mitosis and differentiation of cells that have receptors for it
 * Tumor suppressor gene**: gene that codes for a protein that ordinarily suppresses cell division
 * Oncology**: study of cancer
 * Carcinoma**: cancer rising in epithelial tissue
 * Sarcoma**: cancer that arises in the muscle and connective tissue
 * Leukemia**: cancer of the blood forming tissues leading to the overproduction of abnormal white blood cells.
 * Lymphoma**: cancer of lymphatic tissue

1. What do cancer cells look like? Cancer cells loon abnormal, that don't look like a epithelial, muscle, nervous, or connective tissue.

2. What is unusual about the nuclei of cancer cells? The nuclei of cancer cells are enlarged and may contain an abnormal number of chromosomes.

3. Why don't cancer cells die? Cancer cells fail to undergo apoptosis even though they are abnormal cells. The undergo a cell cycle an unlimited amount of times.

4. Describe the three phases of the development of cancer. The development of cancer is a multistage process.
 * 1) **Initiation**: a single cell undergoes a mutation that causes it to begin to divide repeatedly.
 * 2) **Promotion**: a tumor develops, and the tumor cells continue to divide. As they divide, they undergo mutations.
 * 3) **Progression**: one cell undergoes a mutation that gives it a selective advantage over the other cells. This process is repeated several times, and, eventually, there is a cell that has the ability to invade surrounding tissues.

5. Mutations in what two types of genes lead to uncontrollable growth? 1. **Proto-oncogenes** code for proteins that promote the cell cycle and prevent apoptosis. They are often likened to the gas pedal of a car because they cause accelerating of the cell cycle. 2. **Tumor- suppressor genes** code for proteins that inhibit the cell cycle and promote apoptosis. They are often likened to the brakes of a car because they inhibit acceleration.

6. What is p53? How does it cause cancer? p53 is a protein that turns on genes to stop the cell cycle and activates repair enzymes. It causes cancer when the proto-oncogene becomes an oncogene, no matter how much p53 there is, none will be available.

7. What is RB? How does it cause cancer? RB turns on the gene for cyclin D and other genes whose products promote entry into the S phase of the cell cycle.

8. What are the most common cancers cases for males and females? The most common cancer cases for males is prostate cancer and the most common for females is breast cancer.

9. What are the most common cancer deaths for males and females? The most common cancer deaths for males is lung cancer and the most common for women is lung cancer as well.