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Mitochondria Are Alive

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Re: Mitochondria Are Alive

#231

Post by im3w1l »

ampdepolymerase wrote: post #127
IAmNotACellist wrote: post #71

The fact that every child on the planet is religiously taught that the mitochondria is the powerhouse of the cell is all the evidence I need that we're upholding a primordial contractual agreement and these are the conditions to which we are beholden. Name a single biological entity that has a better PR department. The only one that comes close is Athlete's Foot, which makes the victim sound cool.

> the mitochondria is the powerhouse of the cell The explanation doesn't get much better at higher levels. You have the Krebs cycle which biology people religiously memorize but it doesn't really explain much either. The actual interesting part is usually handwaved away as "magical enzyme/protein" catalysis. Understanding how the mitochondrial proteins/enzyme catalysts function would usually require a graduate degree…

If you haven't, I suggest you look up an on how ATP Synthase uses the proton gradient to create ATP. It's quite amazing. It's literally a little nano-machine.

Re: Mitochondria Are Alive

#232

Post by mock-possum »

JumpCrisscross wrote: post #209
liyamchitayat wrote: post #185

Earlier quoted context omitted.

Hi! I agree with you, which is why I wrote this- but if you google "are mitochondria alive" gemini says it isn't. And yes, the cells in your heart have an effective and potenitial niche! We seem to have many tools to engineer viruses, but few to engineer mitochondria- perhaps considering them as alive could change that!

> if you google "are mitochondria alive" gemini says it isn't And my grandmother is a bicycle.

Still one of my favorite idioms

Re: Mitochondria Are Alive

#233

Post by beambot »

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…

> 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 body. If I relocate you to the moon without support infrastructure, you would die too -- and yet (I think?) you are probably alive.

Re: Mitochondria Are Alive

#234

Post by adastra22 »

twothreeone wrote: post #46
adastra22 wrote: post #37

Earlier quoted context omitted.

Organelles are alive too. All active biological systems are alive. Mitochondria have for many generations now been known to have their own DNA and replicate on their own. So I’m not sure what new distinction is being drawn?

I _think_ what they mean is it's not typically listed as a "life form" in its own right, i.e., there's no Domain under which one would classify Mitochondria - maybe just calling them bacteria would capture the article's intent? So, the modification would be that we are living in symbiosis with mitochondrial bacteria, similar to how we live in symbiosis with our gut bacteria, rather than them being classified as "orga…

As others note, it is classified in the tree of life. We know approximately what kind of bacteria it evolved from, and mitochondria themselves constitute their own divergent branch of the tree of life (there are many longitudinal studies of mitochondria across species).

But if you wanted classify them based on functionality rather than evolutionary history, I'd say they're more like viruses. They have only a handful of genes themselves, and exploits the nucleus' genetic material for all the other proteins it needs to function.

Re: Mitochondria Are Alive

#235

Post by crazygringo »

rsync wrote: post #125
roncesvalles wrote: post #119

It's such highly unlikely chance events that make me think we really are alone in the universe (we = a sentient civilizational lifeform). There's just no way the long series of extremely improbable events that led to our rise was replicated anywhere else, and it took the sheer vastness of this universe for it to have emerged even once.

There is ~1M bacteria in a single drop of seawater. Now multiply that by (the ocean) and multiply the interactions by X billion years. It seems impossible for a symbiosis like this not to have happened . No matter how low the odds are, the counts of those potential interactions bring this outcome to a certainty.

> No matter how low the odds are, the counts of those potential interactions bring this outcome to a certainty.

That is simply not true. Events are classified by probabilities, and there are a whole lot of things with a probability a lot less than will happen across the whole ocean across however many billion years.

All the higher-probability events will occur, yes. But a specific sequence of multiple extremely low-probability events? That then continues to replicate before it gets wiped out by chance?

Not a certainty, absolutely not. Contrary to what you say, it matters very much exactly how low the odds are.

Re: Mitochondria Are Alive

#236

Post by bonzini »

thinkling wrote: post #222
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…

> Most of their genes, the code for their structure, are in the nuclear DNA. Are they? I was under the impression that mitochondria are closer to pseudo-cells living inside human cells. Wikipedia seems to confirm this [1]: > Although most of a eukaryotic cell's DNA is contained in the cell nucleus, the mitochondrion has its own genome ("mitogenome") that is substantially similar to bacterial genomes. [1] https://en.w…

See below on Wikipedia: "Most proteins necessary for mitochondrial function are encoded by genes in the cell nucleus and the corresponding proteins are imported into the mitochondrion. The exact number of genes encoded by the nucleus and the mitochondrial genome differs between species."

Re: Mitochondria Are Alive

#237

Post by [deleted] »

kylebenzle wrote: post #227
thinkling wrote: post #222

Earlier quoted context omitted.

> Most of their genes, the code for their structure, are in the nuclear DNA. Are they? I was under the impression that mitochondria are closer to pseudo-cells living inside human cells. Wikipedia seems to confirm this [1]: > Although most of a eukaryotic cell's DNA is contained in the cell nucleus, the mitochondrion has its own genome ("mitogenome") that is substantially similar to bacterial genomes. [1] https://en.w…

OP above you is correct. Maybe you are thinking about it wrong?

[deleted]

Re: Mitochondria Are Alive

#238

Post by adastra22 »

dekhn wrote: post #50
adastra22 wrote: post #37

Earlier quoted context omitted.

Organelles are alive too. All active biological systems are alive. Mitochondria have for many generations now been known to have their own DNA and replicate on their own. So I’m not sure what new distinction is being drawn?

Depends on your definition of organelle (whether you limit it to plastids/mitochondria, both of which were derived from external independent living cells, or use a more expansive definition that includes more cell compartments that weren't derived from independent living cells). General acceptance of the endosymbiont theory is a relatively recent (much less than 50 years) phenomenon.

"General acceptance" is a subjective criteria. But the endosymbiont theory is >60 years old at this point.

Re: Mitochondria Are Alive

#239

Post by ale42 »

thinkling wrote: post #222
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…

> Most of their genes, the code for their structure, are in the nuclear DNA. Are they? I was under the impression that mitochondria are closer to pseudo-cells living inside human cells. Wikipedia seems to confirm this [1]: > Although most of a eukaryotic cell's DNA is contained in the cell nucleus, the mitochondrion has its own genome ("mitogenome") that is substantially similar to bacterial genomes. [1] https://en.w…

There's a specific page on Wikipedia about Mitochondrial DNA [1], where it is clearly said that:

  In the cells of extant organisms, the vast majority of the proteins in the
  mitochondria (numbering approximately 1500 different types in mammals) are
  coded by nuclear DNA, but the genes for some, if not most, of them are
  thought to be of bacterial origin, having been transferred to the eukaryotic
  nucleus during evolution. (citing [2])
[1] https://en.wikipedia.org/wiki/Mitochondrial_DNA

[2] https://doi.org/10.1016%2Fj.cels.2016.01.013

Re: Mitochondria Are Alive

#240

Post by adastra22 »

outworlder wrote: post #80
marcosdumay wrote: post #36

Earlier quoted context omitted.

> mitochondria were thought to just be a component of the cell. ... hundreds of years ago, for a short time after they were discovered. We know that they behave like bacteria for almost as long as we know that they exist.

They "behave as" bacteria. Are they bacteria? Are they 'alive' by themselves? That's the distinction.

What do you mean by "alive?" Because of course they are alive, regardless of whether you consider them bacteria or not. There is a strange definition of "alive" that is being used by you and the author article that I'm not understanding.

If a mitochondria is not "alive," then is it dead? Even if it is taking part in an active, living cell?

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