I don’t get why is possible to regrow a lot of stuff (skin, muscles, broken bones etc.), but only to a certain extend. At one moment you are suddenly not able to rebuild things.

Why is that and what determines what we can regrow?

  • NoneOfUrBusiness@fedia.io
    2·
    13 小时前

    It’s still an ongoing area of research about why this happened

    Wouldn’t the obvious answer be “because cancer”?

    their division is very tightly controlled, and even then they are the source of the most common cancers in humans

    Can you give examples?

    • Contramuffin@lemmy.world
      3·
      11 小时前

      wouldn’t the obvious answer be cancer

      Sure, but that’s a bit of a teleological reasoning. Not to mention, there are many ways to avoid cancer without removing stem cells from the vast majority of a species’ life history. Beyond that, people are also concerned about what specific mutations led to mammals’ inability to keep stem cells around, because this knowledge would directly help with our ability to generate stem cells in the lab.

      examples

      Intestinal and stomach cancers, for instance, have a lot to do with the stem cells in the intestinal/stomach lining. You can also debate whether the progenitor of skin cells counts as a stem cell. In general though, I think this statement is really just a slightly-more-detailed restatement of the general observation that tissues that experience a lot of turnover are more likely to develop into cancer