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Mitochondria Are Alive

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Re: Mitochondria Are Alive

#271

Post by dekhn »

quantadev wrote: post #251
dekhn wrote: post #247

Earlier quoted context omitted.

Interesting argument, but nobody believes that a diverse chemical makeup is sufficient to guarantee life. You can wave big numbers around but none of that makes a convincing argument; it's not hard to construct any number of scenarios where self replicators are started but don't lead to true life. Also you're comparing a gram of water to a bunch of bases; H2O is not DNA.

Sure we don't have proof that all life will form from essentially "binary" data, (although technically ours is made of 4 bases, not 2), but it's almost axiomatic that life will find the simplest possible way to store information before it finds the more complex ways. Ergo DNA is almost binary, but quarternary instead. It's nearly digital. Insofar as your H20 vs DNA comparison, I merely used water as a way to show rel…

Are you aware that at high concentrations, DNA, RNA, and proteins all have serious problems? For example, DNA and RNA are highly charged, with strong repulsion effects, while also having large greasy areas. At the concentrations you're describing, the DNA and RNA would not be functional as we know it.

Re: Mitochondria Are Alive

#272

Post by TheHegemon »

positus wrote: post #265
dukeofdoom wrote: post #261

Earlier quoted context omitted.

"Sperm and egg cells, known as gametes, fuse during fertilization to create a zygote. " Since all humans were just 2 cells at one point. It seems to follow that the entirely of the code for what a human is, is contained in just those 2 cells. Not just code for a finger. But even code for our deeply ingrained fear of snakes. Was just at one point contained in those 2 cells. Kind of blows your mind. If they are separat…

[flagged]

Are miscarriages then involuntary manslaughter?

Re: Mitochondria Are Alive

#273

Post by amelius »

beambot wrote: post #233
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…

> This accurately describes much of science...

It is more related to the philosophy of science.

https://en.wikipedia.org/wiki/Philosophy_of_science

Re: Mitochondria Are Alive

#275

Post by jibal »

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).

Re: Mitochondria Are Alive

#276

Post by RajT88 »

positus wrote: post #265
dukeofdoom wrote: post #261

Earlier quoted context omitted.

"Sperm and egg cells, known as gametes, fuse during fertilization to create a zygote. " Since all humans were just 2 cells at one point. It seems to follow that the entirely of the code for what a human is, is contained in just those 2 cells. Not just code for a finger. But even code for our deeply ingrained fear of snakes. Was just at one point contained in those 2 cells. Kind of blows your mind. If they are separat…

[flagged]

It would be a so-so argument if it was true. (It is not) How DNA is expressed is a part of the story as well which involves many environmental factors both in utero and after birth.

We do not totally understand how it works, but there are heritable traits not passed via DNA - the one often in the news is women with emotional trauma pass that trauma on to their children, and those children show those symptoms even if raised in a happy home with 0 contact with the mother.

It is a philosophical argument, not a scientific one. One which if we try and reason based on how special nature treats embryos quickly falls apart anyways...

Re: Mitochondria Are Alive

#277

Post by incompatible »

positus wrote: post #265
dukeofdoom wrote: post #261

Earlier quoted context omitted.

"Sperm and egg cells, known as gametes, fuse during fertilization to create a zygote. " Since all humans were just 2 cells at one point. It seems to follow that the entirely of the code for what a human is, is contained in just those 2 cells. Not just code for a finger. But even code for our deeply ingrained fear of snakes. Was just at one point contained in those 2 cells. Kind of blows your mind. If they are separat…

[flagged]

In that case, it would also be a good argument against killing any single-celled organism, since it's a life that already exists. But life on Earth is cheap.

Re: Mitochondria Are Alive

#278

Post by elcritch »

TeMPOraL wrote: post #269

Random thought after reading all the philosophical and semantics tangents in the comments here: A good example of a memetic equivalent of endosymbiosis could be Christianity - Catholicism in particular. Historically, as Christianity spread around the world over the two millenia, it would often adapt and absorb indigenous beliefs and practices of converted populations[0]. Many would die out over time, but some got int…

> Historically, as Christianity spread around the world over the two millenia, it would often adapt and absorb indigenous beliefs and practices of converted populations

Certainly, in the Eastern Orthodox church it's commonly called "baptizing the culture". The idea was/is to take what is good from a culture and to incorporate it to help people become Christians. Also it's a core part of Christian missionaries to learn the language and translate the scripture, and if needed to create a written form of the language.

So I'd agree Christianity has always been a bit of a symbiosis of cultures, analogous as you said to endosymbiosis. It started purely Judaic, incorporated large parts of hellenism, and spread globally and imported more bits. The Jewish and Hellenic pieces aren't completely mixed, sort of similar to a mitochondria actually.

Then again it makes sense of a religion with a core belief that God became man and created a symbiosis of the two as their savior.

Re: Mitochondria Are Alive

#279

Post by addaon »

JumpCrisscross wrote: post #201
aydyn wrote: post #198

Earlier quoted context omitted.

Does it yield a rare Earth? If we didn't have mitochondria and had something say 20% less efficient, why couldn't multicellular life still exist?

> why couldn't multicellular life still exist? We don't know the fundamental energy requirements of complex life. The threshold may be 2%. It may be 19.995%. If non-mitochondrial metabolism is common, the Earth would still be rare in that we'd be the "fast" biosphere. The high-octane species. Given how power-intensive intelligence is, that might be material. (Or it might not.) More fundamentally: we have no plausible…

> Given how power-intensive intelligence is

I’m not convinced there’s a reason to think intelligence is inherently power-intensive. Based on our limited samples, it’s certainly energy intensive, but there’s no reason it couldn’t be slowed down. In a world with less power available to life, one would expect speeds of e.g. predators and prey to be slower, allowing a slower intelligence to still provide an advantage.

Re: Mitochondria Are Alive

#280

Post by quantadev »

dekhn wrote: post #271
quantadev wrote: post #251

Earlier quoted context omitted.

Sure we don't have proof that all life will form from essentially "binary" data, (although technically ours is made of 4 bases, not 2), but it's almost axiomatic that life will find the simplest possible way to store information before it finds the more complex ways. Ergo DNA is almost binary, but quarternary instead. It's nearly digital. Insofar as your H20 vs DNA comparison, I merely used water as a way to show rel…

Are you aware that at high concentrations, DNA, RNA, and proteins all have serious problems? For example, DNA and RNA are highly charged, with strong repulsion effects, while also having large greasy areas. At the concentrations you're describing, the DNA and RNA would not be functional as we know it.

Right. The "thought experiment" math is a tight packing of theoretical RNA molecules, and not intended to be taken literally, without a dilution factor; but only to show [some] people their intuition is WAY off about the power of large numbers to "create" unlikely patterns.

For example, if you ask most people how many randomly occurring Rubiks Cubes will just be accidentally solved even with Avogrdro's number of them, their answer is usually zero; and unsurprisingly they're the same ones claiming there had to be a God to create even the initial replicator.

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