as stated in title, for example, why do red blood cells live and die in a matter of a few months, but cardiac and oocyte cells last for up to 50 years? i understand it has to do with telomeres somewhat, but vaguely. can anyone elaborate?
In: 24
Usually, the cells that have a long lifespan have structures that make it prohibitively difficult for the body to replace them. When dealing with heart cells and neurons, for example, removing one of them has consequences for either the structure that they’re a part of or for the extremity that they’re attached to. Their associated organ doesn’t function properly until a new cell comes in to do the job of the old one. And the organism could more easily die before that happens.
Blood cells and epithelial cells, on the other hand, are specifically designed to be lost. Your epidermis and your intestinal lining undergo a lot of mechanical friction and/or damage. The body might have the option of making them more resistant to that damage, but that would work against their absorptive or regulatory functions that are also necessary for its systems to work.
Blood, likewise, has a tendency to leak out when something is damaged, so it’s better to constantly replace old cells rather than just let them keep working. In fact, the destruction of old blood cells is necessary for production of bile and other necessary chemicals. What’s more, the red blood cells of warm-blooded animals have their nuclei destroyed when they’re originally created so that they can contain more hemoglobin to fuel the body. So, even if it were a good idea to save the cells for as long as possible, there’s no way to really do so.
So, yeah. The cells live longer or shorter depending on what they’re meant to do.
Latest Answers