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Aim : What are cancer cells?

Monday, February 11 th , 2013. Do Now: Complete the fill in the blank work sheet on “Mitosis and Cell Division”. Aim : What are cancer cells?. A little review…. A gamete is a sex cell. Sperm and ova. Haploid or Diploid?. A Somatic cell is a body cell.

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Aim : What are cancer cells?

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  1. Monday, February 11th, 2013 Do Now: Complete the fill in the blank work sheet on “Mitosis and Cell Division” Aim: What are cancer cells?

  2. A little review…. • A gamete is a sex cell. • Sperm and ova. Haploid or Diploid? • A Somatic cell is a body cell. • skin cell, cardiac cell, liver cell, etc. Haploid or Diploid?

  3. Meiosis • Only occurs in “gonads” (ovaries or testes) • Only produces “germ” cells (reproductive cells) • Involves 2 divisions • 1cell2 cells4 cells • Cuts the # of chromosomes per cell in half • Daughter cells receive a variety of different genetic combinations • These cells are genetically SIMILAR but NOT genetically IDENTICAL to the Parent cells. • * They share the genes from “mom and dad”

  4. Mitosis • “Body Cells”- Occurs all over the body • Produces all “somatic” (non-reproductive) cells. • Completed in 1 division • 1 cell  2 cells • maintains the same # of chromosomes per cell • Daughter cells are genetically IDENTICAL to the original. • Think about it: • If you need to make more skin cells, you want them to be just like your original skin cells. The somatic cells made need to be IDENTICAL.

  5. Mitosis Interphase: chromosomes replicate Prophase: spindles and centrioles form Metaphase: chromosomes line up in the Middle. Anaphase: sister chromatids start to move to opposite poles. Telophase: nuclear membrane reforms Cytokinesis: 2 daughter cells are made, identical to the original parent cell.

  6. Mitosis

  7. Mitosis vs. Meiosis

  8. Cancer • Caused by uncontrolled cell division • Cancer cells don’t function normally, invade other tissues, monopolize nutrients, and replace normal cells • Metastasis:the spread of cancer cells to other areas of the body • Cancer cells often spreadthrough: • lymphatic system or bloodstream

  9. What are Oncogenes? Oncogenes: are genes that, when mutated or expressed at high levels, helps turn a normal cell into a tumor cell. • Tumor: solid mass of cells • All cancers result from genetic changes (mutations) in the genes which regulate cell division.

  10. Causes of Oncogenes being turned on: • Chromosome replication errors 2. Viruses 3. Carcinogens (Mutagens)

  11. Normal Cell Division versus Cancer Cell Division

  12. Risk factors for cancer: • Family History • - you can inherit cancer genes • Aging • - increases chance of random errors and cell damage - Impaired Immune System - a healthy system may destroy cancer cells, so stay healthy! - stress and disease can impair immune responses - Exposure to Carcinogens - 85-90% of cancers are caused by carcinogens - UV radiation • Lifestyle • - smoking, diet, etc.

  13. Smoking • Increases risk of cancer in: • lung, throat, mouth, bladder,& liver • (also a major risk factor for cardiovascular diseases ) • Chances of living to 80 in USA: • non-smokers 57%; smokers 30% • Difference in life expectancy: • 15 years less for smokers

  14. Diet There are many things that increase the risk for cancer: 1. Food additives (preservatives, pesticides, dyes and sweeteners) 2. High fat diets (obesity) • 3. Low fiber diets and low anti-oxidant diets can increase the risk of cancer, including colon cancer. • - fruits, grains and vegetables are high in fiber and anti-oxidants

  15. Assessment:

  16. Tuesday, February 12th, 2013 Aim: What are the differences between asexual and sexual reproduction? Do Now: Answer this…. How does a healthy cell become a cancer cell? (Use your notes from yesterday)

  17. What is a clone? Clone: A genetically identical cell

  18. How to clone an adult mammal: • Take an embryonic “stem” cell, remove the nucleus then add a nucleus from adult • Implant new cell into female for development • How to clone a plant: • Split up cells from existing plant • Use “tissue culture” to grow complete plants from each cell

  19. But HOW are clones produced? • Clones are produced naturally by mitosis • Clones can be produced by genetic engineering

  20. Rat Pigs Wolf Horse Cloning for food Rabbit Sheep Water Buffalo

  21. Genetically Engineered Cloning • Remove the haploidnucleus from an ova & the diploidnucleus from a somatic cell • Insert the diploidnucleusinto the donor ova • Now we have a diploid ova (zygote) Rapid mitosis will occur!!

  22. What is Asexual Reproduction? A new organism (sometimes more than one new organism) is produced from one organism. • Only oneparent is needed to reproduce asexually. • In most cases: • Mitosisis the only type of cell division involved

  23. With Asexual Reproduction….. The new organism will have hereditary material identical to the hereditary material of the parent organism. Offspring are genetically identical to parent

  24. So, what is the difference between asexual and sexual reproduction? • Asexual Reproduction: • Reproducing without the interaction of 2 sexes, one parent needed. • The make up of offspring is genetically IDENTICAL to the parent. • Cell division process: MITOSIS • Sexual Reproduction: • Fusion of 2 gametes (sperm and egg). • The make up of offspring is genetically similar, different genes though. • Cell division process: MEIOSIS

  25. Assessment: Read textbook page 250-252. Complete “Reading Check” on page 251 & 252

  26. What are the 6 different types of Asexual Reproduction? • Binary Fission • Budding • Sporulation • Regeneration • Rhizomes • Tubers

  27. 1. Binary Fission • Organism splits into two equal halves • Most common method of reproduction in unicellular organisms (BACTERIA)

  28. offspring grows from a “bud” on surface of larger parent • will eventually break off and live independently • occurs in: yeast, hydra (small animal) and many plants • Budding vs. Binary Fission? • budding divides living material unevenly 2. Budding

  29. 3. Sporulation • spores are released in large numbers and are carried by wind or water • can survive conditions that kill off parent • - produced by many plants and fungi (molds & mushrooms)

  30. 4. Regeneration • ability to replace missing body parts • occurs in all organisms to some degree • - can only produce new organisms in simpler species

  31. 5. Rhizomes • underground stems produced by plants • - As these stems grow through the soil, they produce more roots which develop into plants

  32. 6. Tubers • - Modified rhizomes • - Start out as a bud or eye on potatoes • Develop into root and • then adult • Examples: potatoe

  33. Name: ______________________________ Class Period: ____ Date: ___________ Asexual Reproduction vs. Sexual Reproduction Let’s record the differences between these 2 types of reproduction:

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