Emma+19.1

Read 19.1 in the book on Cancer Cells. Define the words in bold on the wiki and answer the questions at the end of the section on the wiki (write the question and your answer).

Bold Words: 1. Cancer- Malignant tumor whose nondifferentaited cells exhibit loss of contact inhibition, uncontrolled growth, and tthe ability to invade tissue and metasize 2.apoptosis- programmed cell death 3.telomeres- special repetitive DNA that cap off chromosomes in human cells 4.tumor- piled up cancer cells that grow on top of eachother with no restraint 5.carcinogenesis- the development of cancer in three phases - Initiation: a single cell undergoes a mutation that causes it to begin to divide repeatedly -Promotion: A tumor develops, and the tumor cell continue to divide. As they divide, they undergo mutations -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 surronding tissues 6.Angiogenesis- the formation of new blood vessels 7. Metastasis-when cells begin new tumors far from the primary tumor 8. Proto-oncogenes- code for proteins that promote the cell cycle and prevent apoptosis. They are often likened o the gas pedal of a car because they cause acceleration of the cell cycle. 9. tumor- Supressor 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 10.Oncogens- when proto-oncogenes mutate they beome cancer causing genes... whatever a proto-oncogen does an oncogene does it better 11.growth factor- signal that activates a cell signaling pathway, resulting in cell division 12.cyclin- protein that regularly increases and decreases in concentration during the cell cycle 13.Oncology- study of cancer 14.oncologist- medical specialist in cancer 15.Carcinomas- cancers of the epithial tissues and adenocarcinomas are cancers of glandular epithial cells. Including skin, breast, liver, pancreas, intestines,lung, prostate and thyroid 16. Sarcomas- Cancers that arise in muscles and connective tissues, such as bone and fibrous connective tissue 17. Leukemias are cancers of the blood 18. Lymphomas- are cancers of the lympathic tissue

Questions: 1. What characteristics of cancer cells allow them to grow uncontrollably: -Cancer cells fail to undergo apoptosis -telomerase is turned on in cancer cells and continues to rebuild telomeres so that the telomeres remain at a constant length and the cell can keep dividing -cancer cells perform angiogenesis, which forms bloodvessels to the cancer 2. Mutations is what two types of genes lead to uncontrollable growth? -proto-oncogenes -Tumor supressor genes 3.What are the most common types of cancer? -Respiratory system- Lung Cancer -Digestive System- colon Cancer -Breast Cancer -Endocrine system- Thyroid cancer -Prostate Cancer -Skin Cancer- Melanoma basal, cell carcinoma