Video Homework Assignment“Cell Biology & Cancer”

Reference Pgs:

Chapter 12: pgs. 229-233

Chapter 19: pgs. 370-374

Video #2: Cancer and its CausesGo to this site: http://www.learner.org/resources/series187.html

Scroll down & Find “ Session 8: Cell Biology & CancerClick on “VoD” and watch

Reference Pages: Ch. 19 Pgs. 370-373

**While watching the video be sure to have a minimum of 15 key statements. Some of your statements should address:

1. What was thought to be the cause of cancer in the earlier years? What do we know today in regards to the causes of cancer?

2. Differences between an Oncogene and a Tumor suppressor gene and what these genes specifically do.

3. The RAS gene and p53 gene and what they do. Which one is a proto-oncogene

4. Why is the p53 gene considered to be the “Guardian Angel of the cell” Give three things that is does.

5. How has the study of Telomeres and the enzyme Telomerase contributed to our knowledge of cancer.

Characteristcs of Cancer

• Cancer is the result of Mutated genes.• Mitosis gone Haywire (uncontrolled cell division)• Cells develop & no longer have their specialized

function (unable to produce what they are supposed to produce)

• All they do is make more cancer cells• Will induce blood vessels to grow (angiogenesis)• Has the ability to spread (metastasize)• Cells will divide and grow into tumors

– Benign (non-cancerous) vs. -Malignant (cancerous)

Genes that Cause Cancer (Pgs: 371-372)• Genes: are the A, T, C, G sequences that are used to make proteins in all of

our cells. When genes get “expressed” a portion of the DNA is used to make a particular protein. *Environmental factors can change how genes get expressed

(**genetic expression = protein synthesis)

• Oncogenes: cause cell division to continue at a faster & faster rate. Other genes are activated that normally are “off”(Ex. From video: ras gene) – seen in 30% of all cancers

• Proto-Oncogenes: normal genes that code for normal cell growth and division

• Tumor Suppressor Genes: normally inhibits cell division and prevents uncontrollable cell growth. Typically, these genes stops tumors from growing. When mutated, this ability is lost.

(Ex. From video: p53 gene) – seen in 50% of all cancer

Apoptosis: Failure of normal cell programmed death Pgs. 800 & 902

Chromosome AbnormalitiesChromosome Abnormalities: Pt. mutations, Translocation, etc (pg. 286)