If you want a fun scifi horror novel to read related to this topic, check out Parasite Eve by Hideaki Sena. It's the novel that inspired the PSX game. The whole plot revolves around mitochondria and was inspired by the author's time as a grad student. I read it a few months ago and really enjoyed it.
Mitochondria Are Alive
361–370 of 412 posts
Re: Mitochondria Are Alive
#362Mitochondria are why I’m a Rare Earther. In Earth’s history, mitochondrial endosymbiosis occurred once. Without that you don’t have the energy budget for complex life. Moreover, there may be a narrow window where it can happen: modern microbiology has defences and selection pressures that it make inhospitable to the hobbling chimeræ the first mitochondrial cells would have been. Until mitochondria, the emergence of l…
Mitochondria seems to have been an 'accident', yes. That does not mean that other lifeforms in different planets require mitochondria or equivalent organelles. As long as they can perform the necessary chemical reactions (which could be different in a different environments) and extract enough energy, they should be good. How did mitochondria evolve in the first place? Could they have remained as independent organism…
> Could they have remained as independent organisms and use their massive energy budget to evolve independently?
There are independent mitochondrial relative. They are mostly parasites that live inside cells.
From https://en.wikipedia.org/wiki/Mitochondrion
> The proto-mitochondrion was probably closely related to Rickettsia.
From https://en.wikipedia.org/wiki/Rickettsia
> Being obligate intracellular bacteria, rickettsias depend on entry, growth, and replication within the cytoplasm of living eukaryotic host cells (typically endothelial cells).
> Most notably, Rickettsia species are the pathogens responsible for typhus, rickettsialpox, boutonneuse fever, African tick-bite fever, Rocky Mountain spotted fever, Flinders Island spotted fever, and Queensland tick typhus (Australian tick typhus).
Re: Mitochondria Are Alive
#363This article is framed as if there is something novel and profound here, but the "aliveness" of mitochondria is simply a matter of how we choose to apply the label "life" - a human linguistic construct that exists independently of the biological phenomena. This is not a new discussion - science has been considering this question for many decades, just as it has with viruses. These all come down to arguments about sem…
> My heart can exist independently of me, and be transplanted into other people, but does it mean that it is alive?
Your heart cannot exist independently of you as a heart. It is only a heart in name, as it does not function as a heart. Its identity as a heart depends on its ability to function as a heart within some organism. The same can be said for any part or organ. A severed hand is a hand in name only. A corpse is not a body, as it no longer functions as one.
A transplanted heart becomes a heart once more. A reattached hand becomes a hand once more. If you think this is weird, then you haven't done your metaphysical homework. Why should it be weird? It could only be weird if you have made certain (unexamined) metaphysical presuppositions. The structure of a heart removed from an organism persists long enough that it can become reintegrated into an organism such that it functions once again as a heart.
But also note that the matter composing a heart itself isn't fixed. About 1% of heart cells are replaced per year in the young. So if function and structure can survive transient material change, and the matter that makes up a heart can assume and lose and reassume its identity as part of a heart, then why can't a heart lose its identity as a heart when removed, and regain its after it is implanted back in?
Re: Mitochondria Are Alive
#364Earlier quoted context omitted.
The strongest arguments against abortion don't hinge on whether the fetus is a person. The question of abortion ultimately boils down to whose rights we privilege: those of the mother, or the fetus?
Why would the fetus have any rights that are not automatically defeated by the rights of its mother if it's not a person? All anti-abortion arguments that I'm aware of start by arguing that the fetus deserves the rights of a person, and then proceed from there. Could you present a counterexample?
Sure, a couple I've come across:
"Potentiality" - this view argues that regardless of whether the fetus is a person, it has the potential to become a person, and thus inherits some moral consideration.
"Value of Human Life" - the argument that human life - at any stage of development - has intrinsic value and thus should be protected.
Re: Mitochondria Are Alive
#365Earlier quoted context omitted.
> The implication of the whole article is that there something we have missed. I think this article is talking to people who haven't internalized the details of the scientific consensus. Those people are still going around, talking about "life" and making decisions based on the flawed understanding this article is critiquing. I think it's likely that the thing that "has been missed" is not narrowly scientific in the…
I am not sure what exactly the 'broad implications and worldview' are here that are being challenged. The article is presented as a scientific opinion and references scientific research and has a doi number for citation (Cite: Liyam Chitayat. “Mitochondria Are Alive” Asimov Press (2024). DOI: https://doi.org/10.62211/38pe-75hu ). What do you think that the article was challenging?
Obviously the article is challenging the view — scientific or not — that mitochondria are not living.
Side note: previously I was funded by NSF and NASA to study such questions from biophysics and astrobiology.
That said, this was a delightful read. I did not realize or conceive of mitochondria as, like bacteria in our bodies, independent living networks with unique genomes, evolution, and flows of information and energy.
Reading about the health benefits of “external mitochondria” made me think about when I hug my dog: are we exchanging mitochondria, perhaps?
Re: Mitochondria Are Alive
#366Earlier quoted context omitted.
I’m not sure what you are arguing against. For me, the article offered a lovely reminder that life is special. Life involves mechanisms but it is more than a machine. And with an attitude that our lives our symbiotically bound to another living organism (or 10^17 of them) we gain a valuable humility — one that might afford us new perspectives on how to make them all happy and flourish. That’s the promise— not just a…
As I said in another comment, I think that mitochondria are fascinating, understudied and a rich area for research. We are bound to the myriad other pieces of DNA that all have different evolutionary histories within us, we are symbiotically bound to many strands of life on many levels. We are just one strand, a part of a singular whole, bound to all strands of life beyond us. This view of life led me to science. I t…
> it just isn't true that mitochondria are alive by our currently accepted definition of alive. This is an old debate in biology that was settled years ago.
Sorry, but that’s an overreach. There are many “accepted” definitions” of life across different scientific fields. According to Wikipedia, there are at least 123 definitions of life — and there is not scientific consensus. Mitochondria are alive based on some definitions and not alive based on others.
https://en.wikipedia.org/wiki/Life
Expecting life to have total autonomy in self-sustainability is absurd. Otherwise somatic cells or even people would be not alive.
And the argument that mitochondria are not alive because they can’t encode all their own proteins — well, I’ll point out that humans can’t produce all amino acids, either. As a thought experiment, if humans couldn’t produce a certain essential protein — and had to rely on a symbiont, would that mean humans weren’t alive?
Finally I’ll point out that Mitochondria can be healthy or flourishing — and they can be sick and die. How can something that is not alive, die?
It’s ok to argue for a narrow definition. But please don’t present this argument as though you are the defender of clear scientific conclusions. There simply isn’t consensus on this across the sciences.
Re: Mitochondria Are Alive
#367This article is framed as if there is something novel and profound here, but the "aliveness" of mitochondria is simply a matter of how we choose to apply the label "life" - a human linguistic construct that exists independently of the biological phenomena. This is not a new discussion - science has been considering this question for many decades, just as it has with viruses. These all come down to arguments about sem…
Are you not "totally dependent" on the air you breathe, the water you drink, the sunlight that gets turned into your food, ...?
Re: Mitochondria Are Alive
#368I once asked a biologist “using today’s understanding, what is life?” She answered with ”the more we learn, the more I ask myself what is biology?”
Re: Mitochondria Are Alive
#369Okay, what about the Earth? If mitochondria are alive, you must also consider the Earth as being alive too. Personally, I think it's a simple answer. Here's my positively b reasoning on the topic for anyone daring enough. It can be a very blurred line, but much of that is our shadow. Mitichondria are more alive than they are dead. Simply because they exist as potential and can go on and are intended for this, for lack of better words. Where as a rock will not come alive, no matter the conditions. We hope.
Maybe we should think of it like we do for other forms of energy and how I be thought we did think of it already but was of biochemical energy expressions. Along with kinetic energy, potential energy, chemical energy. Surely there is a number determined for the maximum lifetime energy output potential (work) of a single mitochondrion. While it is plain and simple, that's just life for you
Re: Mitochondria Are Alive
#370Okay, what about the Earth? If mitochondria are alive, you must also consider the Earth as being alive too. Personally, I think it's a simple answer. Here's my reasoning on the topic for anyone daring enough. It can be a very blurred line, but much of that is our shadow. Mitichondria are more alive than they are dead. Simply because they exist as potential and can go on and are intended for this, for lack of better words. Where as a rock will not come alive, no matter the conditions. We hope.
Maybe we should think of it like we do for other forms of energy and how I be thought we did think of it already as biochemical energy expressions. Along with kinetic energy, potential energy, chemical energy. Surely there is a number determined for the maximum lifetime energy output potential (work) of a single mitochondrion. While it is plain and simple, that's just life for you.