On pages 185-186, Doctor Moalem described how cellular reproduction is limited due to the presence of a genetic buffer known as telomeres. When the telomeres at the ends of DNA run out, then cell deaths occurs but it also protects us from a disease like cancer. This relates to Big idea 2: Biological systems store, retrieve, transmit, and respond to information essential to life processes.
Explain exactly how the presence of telomeres helps to prevent cancer by giving a brief definition of cancer and stating how DNA uses them to prevent this specific disease. Explain how the presence of telomerase in a cancerous cell help them avoid the function of telomeres. Although the over presence of telomerase in cell causes cancer, how could this enzyme be used by scientists to potentially make future humans live forever without accidentally causing cancer? Find out if some cells tend to have longer telomeres compared to others, and if so, indicate which ones and why this would happen? Also, why do larger species of animals tend to have longer life expectancy compared to smaller species?
Prince Morkeh (pmorkeh4@student.d125.org)
On pages 185-186 Dr. Sharon Moalem describes cancer and its relationship with telomeres. Cancer is a term used for diseases in which abnormal cells divide without control and are able to invade other tissues. Cancer cells spread to other parts of the body through the blood and lymph systems. There are more than 100 different types of cancer. Telomeres are used to help prevent cancer because cells die or lose the ability to reproduce when they run out of telomeres. So, this would help prevent cells from reproducing uncontrollably because eventually they will lose their ability to reproduce because of telomeres. The usage of telomeres is called the Hayflick limit. Big Idea 2 (biological systems store, retrieve, transmit, and respond to information essential to life processes) is connected to this because data is transmitted when the telomeres are gone and this leads to the possible death of the cells. This also connects to our DNA and The Cell Cycle unit (unit 4).
ReplyDeleteTelomerase is used in cancerous cells to help avoid the function of telomeres. It lengthens telomeres at the end of chromosomes so the cell can reproduce forever. This would allow cancerous cells to reproduce uncontrollably. However, telomerase also can benefit humans. Telomerase could potentially make humans live forever because it could keep adding telomeres to somatic cells and it could prevent the aging process in humans. This would allow the cells to potentially never die and could cause humans to live forever. However, some people think having cells live forever would cause problems. Juli Feigon, a UCLA professor of chemistry and biochemistry, says “telomerase is not very active in most of our cells because we don’t want them to live forever. After many generations, DNA damage builds up and we wouldn’t want to pass those errors on to subsequent cells.” So, damages to DNA could provide problems for humans living forever in the future.
Some cells have telomeres that are longer than the average cell. An example of this is stem cells. This is because they are acquired along the in vitro derivation of the stem cells. The reasoning behind this is the expression of a specific telomeric protein during the derivation is greatly increased and this affects the lengthening of the telomere. Larger species of animals tend to have a longer life expectancy than smaller species because they are harder for predators to eat. It is probably more difficult for a predator to take down a smaller animal than a larger one because having a larger body size can be advantageous for defense. However, there are many exceptions such as humans. They live longer than any other mammal and are certainly smaller than other mammals such as elephants or horses.
(Tyler Hagen-thagen4@students.d125.org)