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Mitochondria Are Alive

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Re: Mitochondria Are Alive

#351

Post by HappMacDonald »

amelius wrote: post #273
beambot wrote: post #233

Earlier quoted context omitted.

> These all come down to arguments about semantics and don't add anything to the science. This accurately describes much of science... > My heart can exist independently of me, and be transplanted into other people, but does it mean that it is alive? The cells that comprise your heart are very much alive, but they will die without support infrastructure. They live, they replicate, they die -- like every cell in your…

> This accurately describes much of science... It is more related to the philosophy of science. https://en.wikipedia.org/wiki/Philosophy_of_science

One might say "natural philosophy"

Re: Mitochondria Are Alive

#352

Post by zero_bias »

jibal wrote: post #275
JumpCrisscross wrote: post #78

Mitochondria 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…

Earth is so rare that there might merely be hundred of billions of others (say, one per galaxy).

There are a lot of sub Neptune planets, the reason why there are only a few earth alike planets is just lack of powerful telescopes and observation time. As technology improves, we’ll find much more planets like ours. Earth is not unique in any way

Re: Mitochondria Are Alive

#353

Post by Symmetry »

WalterSear wrote: post #219
outworlder wrote: post #86

Earlier quoted context omitted.

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? This presumes that their energy budget was massive to begin with, rather than being selected for over time.

It's more that cells can have large numbers of mitochondria than that teach produces a large amount of power. Prokaryotic cells can grow large, but because they respirate over their surface they are energy limited.

Re: Mitochondria Are Alive

#354

Post by Symmetry »

jjk166 wrote: post #205
JumpCrisscross wrote: post #78

Mitochondria 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…

This process, known as primary endosymbiosis, happened at least twice, for mitochondria and chloroplasts. Further, while all chloroplasts (and more widely plastids) appear to share a common ancestor, there is evidence that mitochondria may descend from multiple lineages that underwent lateral gene transfer and/or convergent evolution. Nitroplasts are a likely another, separate instance of primary endosymbiosis. There…

The first time it happened involved a huge number of changes in the host cell, like the creation of a nucleus. That makes it seem more likely that an already eukaryotic cell can more easily incorporate other endosymbiotes.

Observation of prokaryote/prokaryote endosymbiosis would be real evidence against the rise of eukaryotes being the or one of the main limitations in the number of intelligent species in our galaxy.

Re: Mitochondria Are Alive

#355

Post by Symmetry »

andrewla wrote: post #54

I read the article waiting for an answer to the question "in what operational sense does this matter?" but it never arrived. The question posed is whether we consider mitochondria to be "alive". It's just a word, who cares. What do we do differently given this assumption?

The question itself if just semantics. But considering our mitochondria as evolving populations subject to selective pressure and genetic drift is really important to understanding their role in our health, down to basic questions like "Why is exercise healthy?"

Re: Mitochondria Are Alive

#356

Post by gcanyon »

This feels a lot like the debate about whether Pluto is a planet: what we're really trying to figure out here is whether we can figure out a definition for a concept that includes all the things we think should be included, and excludes all the things we think should be excluded -- and the meta conversation is: can we all agree on what should be included/excluded? That's a bit of a dance, since a cleaner and simpler definition can swing people's opinion about inclusion/exclusion, so the influence goes both ways.

Re: Mitochondria Are Alive

#357

Post by FollowingTheDao »

Tor3 wrote: post #350
amy-petrik-214 wrote: post #317

Earlier quoted context omitted.

Yea I would def. not call mitochondria "alive" since they are so deeply integrated with the rest of the cell & vice versa. mito is like principle derives from the concept of "the selfish gene" or "the red queen" these famous books on the topic. Arms races between X and Y chromosome. Arms race between nucleus and mitochondria, and so on. or put it this way. why do all animals have sex? because it generates gene sequen…

I don't understand this definition of "alive". Isn't every cell in my body alive? There are definitely differences between an alive cell and a dead one.

> There are definitely differences between an alive cell and a dead one.

Energy flow is the difference. but then everything has an energy flow. Losing and gaining electrons. So it is possible that literally everything is alive, don’t you think? Maybe the problem is is that we’re trying to make a definition where none ultimately really exists.

Re: Mitochondria Are Alive

#358

Post by freetime2 »

blurbleblurble wrote: post #330
meneton wrote: post #179

This 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…

It's wild to me that today's popular biologists like Michael Levin don't give Lynn Margulis credit in every single podcast/interview.

Can you elaborate on this comment? What should popular biologists like Michael Levin be saying on every podcast/interview and why? Serious question from someone who is familiar with Lynn Margulis but not Michael Levin.

Re: Mitochondria Are Alive

#359

Post by Kalanos »

Consider that there are thousands of mitochondria (MT) in an individual muscle cell. Cell diagrams often make it look like there is one MT organelle. It's highly misleading.

Single cell bacteria have thousands of genes. MT have a few dozen genes. Many of the genes that regulate MT are contained in the cell's nucleus.

Re: Mitochondria Are Alive

#360

Post by ambyra »

Today I learned that mitochondria are the only organelles that replicate “on their own” inside a cell, while the other organelles just bud off the preexisting ones. I wonder how they are signaled to do so though.

Reminds me of sea slugs that eat plants and then integrate their chloroplasts to produce energy, or my dad who kept swapping the same Honda motor through all our go karts because it was too good to get rid of.

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