1. In class this week we talked about what may be an important part of cell "senescence" (the process by which they grow old and die). Give a brief overview of how telomeres appear to be related to cell aging, and speculate on why this could contribute to the inability of researchers, prior to the discovery of HeLa cells, to culture cells. How might an understanding of telomeres and telomerase help understand the nature of Henrietta's "immortal" cells?
2. In chapters 14 - 16, the author spends a lot of time discussing the conditions under which Henrietta's children grew up. What do you think her purpose is in disclosing this detailed information?
1. Telomeres are the ends of your DNA which contain non-pertinent genetic information, and we have evolved to possess telomeres because during DNA replication, a bit of our coding in shaved off, and the telomeres serve as a buffer to prevent precious and important genetic material from being lost. When your telomeres start to run out, you start losing valuable genetic material, which starts to wreak havoc with your cells. Normal human cells lack telomerase to rebuild their telomeres, and therefore they die very rapidly in culture. Telomeres and telomerase are the key to understanding why Henrietta's cancer cells are immortal.
ReplyDelete2. Clearly this section seeks to illustrate how the Lacks family didn't get any money from her cells, which the author seeks to convey as a great injustice.
Telomeres are parts of chromosomes that contain nucleotides that do not code for any production of amino acids. During DNA replication, a small piece of DNA from the lagging strand cannot get replicated, so over time, the DNA strand gets shorter and shorter. Telomeres are important because they protect the vital genetic information from being lost after DNA replication. Scientists and researchers have proven that as people age, the length of their telomeres becomes shorter.
ReplyDeleteIn terms of Henrietta’s cells, they are “immortal” most probably because they produce a sizeable amount of telomerase, which keeps them from dying off.
I think the author makes a point to disclose information about Henrietta’s kids in order to show how the legacy of her cells far outlived her actual life and her family. A part of Henrietta’s life was taken away from her and society gave no credit to her story or upbringing. Basically, she was a black woman being exploited by science and researchers.
Chromosomes contain a piece at the end of each of their strands that are called telomeres. Telomeres do not code for anything important. If they did, then precious genetic material could be cut off during the process of DNA replication. Instead, telomeres contain a repetitive coding that is not significant to any genetic material and is solely used in order to act as armor so that the actual genetic material within the chromosome does not become damaged. Telomeres are comprised and created by an enzyme called telomerase. Usually, telomerase cannot rebuild the telomeres so, over time, the telomeres begin to fray and disappear, similarly to a shoes string. This is what causes people to age over time. It is a type of aging process that was evolutionarily created. Henrietta's cells are an anomaly to the usual fraying of the telomeres because her cancer cells produce a large amount of telomerase were allows the telomeres to keep rebuilding instead of fraying.
ReplyDeleteThe author adds this information about how her children grew up to show how they were ignored by society. Even though her immortal cancer cells have given rise to many vaccines and discoveries, her family has gotten little to nothing for this. This shows that science took what was not rightfully theirs and used it for their own advantage. I believe the author found this extremely important to add.
Emma Lasky
ReplyDeleteTelomeres, which are sections of DNA at the ends of chromosomes, which protect our genetic information, allowing for cell division. Each time cells divide, telomeres get shorter. When they get too short, the cells become senescent, or die. If the telomerase can be used to make cells immortal, then telomeres have a strong connection to aging.
ReplyDeleteI think that the Author added this information in to show that even though her cells caused a breakthrough in scientific research, she and her family received little credit or money for it.
Telomeres are at both ends of the DNA strand and don't code for anything. Telomeres do code, but they code for more non important things in the DNA that doesnt't affect much. Telomeres can determine ones age because as they get older they shorten up and have divided more. If the telomeres get too short they have the possibility of dying. This would also affect a real human being. During the aging process telomeres begin to cut down and also disappear which means the body has not choice but to grow older. Henrietta's cells were very unique and special because they had a higher amount of telomeres which meant that her body took longer to age which meant that her cells would live longer.
ReplyDeleteI think he added this information to prove what kind of worth these children were in the real world. They didn't mean anything to anyone and this is also another reason why this whole scientific dilemma exists.
1. Telomeres are located at the end of DNA strands (similar to the ends of shoelaces) and prevent the ends from fraying or sticking together. Telomeres help prevent the loss of genes/ DNA in DNA replication. Telomere ends are shortened after every DNA replication process. When we are younger we have longer telomere ends and as we age the telomere ends become shorter. For example in human blood cells, the length of a telomere ranges from 8,000 at birth to about 1,500 in an older person. Once the telomeres are gone genetic information is lost which causes signs of aging in. Telomerase is the enzyme that builds new telomeres but production drops as we age. There are high amounts of telomerase in some cells including cancer cells and up to 80% of all tumors produce telomerase. The fact that Henrietta’s cells are “immortal” could have to do with the fact that they produce large amounts of telomerase which keeps them from dying and allows them to be “immortal.”
ReplyDelete2. I think that the author such a large amount of time discussing the conditions in which Henrietta’s children grew up in to show that although Henrietta’s cells helped make major advances in science, her children never received any information about what their own mothers cells were doing and how they were being used. Besides the lack of information they were given it shows that they were given no financial compensation for the cells of their mother.
From Kai
ReplyDelete- Telomeres are on the ends of your DNA strand. They are there because during DNA replication your chromosomes get smaller, the telomeres are there so when your chromosomes are shortened you don’t lose any important genetic information. Telomerase is the production on telomeres, in a normal cell as you get older the production of telomeres decrease. However, it could be the case that in Henrietta's cells, she has a much higher rate production of telomerase that never slowed down.
- I think her purpose for disclosing the information of Henrietta's children because she is trying to show and protect the fact that Henrietta was treated bad and her children weren’t given any money for their mothers immortal cells