Read the press release on the 2001 Nobel Prize. Summarize in a few paragraphs the accomplishments of these scientists, and the relevance of their discoveries. (Answer in 500 words or less. Send to instructor) The Nobel Prize in Physiology or Medicine 2001 was awarded jointly to Leland H. Hartwell, Tim Hunt and Sir Paul M. Nurse “for their discoveries of key regulators of the cell cycle”. They have identified key molecules that regulate the cell cycle in all eukaryotic organisms, including yeasts, plants, animals and human.
These fundamental discoveries have a great impact on all aspects of cell growth. Defects in cell cycle control may lead to the type of chromosome alterations seen in cancer cells. This may in the long-term open new possibilities for cancer treatment. 2. Read the FAQ about skin cancer from The Skin Cancer Foundation and the Center for Disease Control and Prevention. Also read about the leading type of skin cancer, basal cell carcinoma, squamous cell carcinoma and melanoma. a) Is skin cancer a concern for you? Why or why not? (Answer in 200 words or less. Send to bulletin board)
Yes, Everyone has some risk of skin cancer. Most skin cancers are associated with ultraviolet radiation from the sun or tanning beds, and many people of color are less susceptible to UV damage thanks to the greater amounts of melanin (the protective pigment that gives skin and eyes their color) darker skin produces. But people of color can still develop skin cancer from UV damage. Additionally, certain skin cancers are caused by factors other than UV such as genetics or other environmental influences and may occur on parts of the body rarely exposed to the sun. ) Based on what you have learned in this lesson, which cells of skin are likely to be the source of cancerous cells? What do you think would happen to the differentiation process in cancerous skin cells? (Answer in 200 words or less. Send to instructor) Differentiation therapy is based on the concept that cancer cells are normal cells that have been arrested at an immature or less differentiated state, lack the ability to control their own growth, and so multiply at an abnormally fast rate. Differentiation therapy aims to force the cancer cell to resume the process of maturation.
Although differentiation therapy does not destroy the cancer cells, it restrains their growth and allows the application of more conventional therapies (chemotherapy) to eradicate the malignant cells. Differentiation agents tend to have less toxicity than conventional cancer treatments. c) Are tanning beds a source of skin cancer? How can you protect yourself from skin cancer? (answer in 150 words or less – send to bulletin board) Yes, research finds people who frequent tanning salons can triple your chances of getting skin cancer.
It is now well established that tanning beds, in addition to other sources of UV radiation, rank among the highest risk sources for melanoma and squamous cell cancer, one of the most aggressive and deadliest cancers. The International Agency for Research on Cancer released a statement last July stating that tanning beds ‘are as deadly as mustard gas, plutonium and other identified carcinogens, stating that tanning beds increase the risk of skin melanoma by 75% when used before the age of 30.
There are various things than one can do to prevent their exposure to artificial sources of ultraviolet rays: Avoid tanning beds and booths. Instead of going to a tanning salon, try tanning sprays. In fact, some salons now provide only tanning spray services. Regardless of your exposure to natural or artificial UV rays, conduct a monthly skin self-exam looking for any abnormalities (like bumps or sores that don’t heal) or moles that have changed size, color or shape. Be sure to check all areas. Visit your physician or a dermatologist to get annual exams.
If caught early skin cancer is now almost 100 percent curable 1. d) Explain the differences between basal cell carcinoma, squamous cell carcinoma and melanoma. (Answer in 200 words or less. Send to instructor) Melanoma is the most deadly skin cancer because it spreads to other areas of the body more readily than the other skin cancers. It is believed that the amount of exposure of the skin to the sun before the age of 20 is actually the determining risk factor for melanoma. Basal cell carcinoma is the most common skin cancer and tends to only spread locally.
Squamous cell carcinoma is the second most common skin cancer, and it can spread to other parts of the body, although not as commonly as melanoma. The risk of getting basal cell carcinoma or squamous cell carcinoma is determined by a person’s lifetime exposure to UV radiation and the person’s pigment protection. 3. Compare and contrast a) the functions of meiosis and mitosis and b) the stages of mitosis and meiosis. Which stage of meiosis (meiosis I or meiosis II) is most similar to mitosis? Justify your answer. (Answer in 500 words or less. Send to instructor) 2.
Meiosis – the division of a cell’s nucleus, ultimately resulting in four daughter nuclei, each with half as many chromosomes as the original nucleus. includes two nuclear divisions meiosis I and meiosis II. Chromosome number is reduced from haploid to diploid. Mitosis – the division of a cell’s nucleus resulting in two daughter nuclei, each with the same number of chromosomes as the original nucleus. Mitosis prophase prometaphase metaphase anaphase telophase cytokenesis usually follows telophase; each new cell is then in interphase Meiosis interphase prophase I prometaphase I metaphase I naphase I telophase I interphase II meiosis II is very similar to mitosis, but it starts with half as many chromosomes. 4. Explain the ways that are used during meiosis to increase the genetic variability of resultant gametes. (Answer in 250 words or less. Send to instructor) Each primary spermatocyte duplicates its DNA and subsequently undergoes meiosis I to produce two haploid secondary spermatocytes. This division implicates sources of genetic variation, such as random inclusion of either parental chromosomes, and chromosomal crossover, to increase the genetic variability of the gamete.