You’re thinking of “life” as if it were a soul, some chemicals gain a “spark of life” and then they are alive.

It’s more helpful to think of life as being those things which reproduce. This isn’t a perfect definition either, of course.

You have a primordial soup full of basic organic chemicals. Some bits of RNA, some proteins, some sugars. These chemicals are already undergoing natural selection, as more stable ones survive longer, but they aren’t undergoing evolution because there is no “descent with modification”. Maybe some chemicals, through chance, form a very simple precursor to a cell which dramatically increases their survival. They can absorb small molecules while protecting themselves from the environment. Great. Does not mean they are alive. Can that structure divide into two parts which can then both grow and divide again? That’s what makes something alive.

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For some reason objects remember their state of motion. This is what Newton's first law says. We do not know why this is the case, just that it is. It is an unsolved puzzle. So either accept it or solve it.

An MVC with 500k base-pairs … that’s quite far removed from self-replicating RNA strands!

I've seen this before, and I understand it, and I understand life can be created spontaneously by lightning striking in the perfect place. But what does that early early, minimal life do?? Is it about to hunt for "food"? How does it survive and replicate if it's just a few proteins that got shocked?

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The issue really comes down to evolution.

The first organisms did not use photosynthesis, but rather chemiosythesis. There is only so simple that you can go if photosynthesis is the only way to produce

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Yes, but there's no 'proven' absolute minimum.

It also depends on what you want the thing to do, and what you call life. If you're just saying 'reproduction in an optimal environment', then the code could be pretty small if placed in a bath of ideal organic molecules.

That said, 1700 base pairs is pretty damned small, and a living environment (with all of its own mechanisms of production) probably is the most optimal environment.

Basically the plans for a virus vs that for bacteria are orders of magnitude in different complexity.

Virus: must have keys to a factory and plans that work in that factory to make more virii.

Bacteria: Must have plans for the entire factory.

I cannot recommend the podcast episode on hybrids on 'in our time' enough if you find the subject interesting. To me it was one of the best episodes they've ever done.

I won't spoil it too much, but I can say that the very idea of speciation is being re-evaluated because of new insights related to hybrids.

If you need super heavy-duty cooling, then phase change systems for water can transfer literally gigawatts of heat power because of how much energy it takes to turn water into steam.

This is effectively what most steam turbine based power plants do after all. A few kg/s through a pipe of steam is many megawatts of enthalpy. If you look at h_fg on a steam table, you can see it's like more than 2 megajoules per kg or so.

For more familiar numbers divide everything by a thousand. Just half a gram of steam per second is over a kilowatt.

It's always some magic term which once you know there's tons of knowledge to consume, thank you, I didn't know it.

By definition, the only category of organism that meets those criteria are primary producers. This is because even a broth of carbohydrates used to culture an organism would need to be produced through photosynthesis, and so would therefore be requiring something made by another organism or ecosystem.

Rather than relying upon nutrients produced by other organisms, primary producers create their own. The most simple known primary producer are Cyanobacteria, and this phylum of microorganisms are thought to have played a key part in terraforming Earth and produce a huge amount of the oxygen we breathe.

Therefore, based on your parameters, I would say, Cyanobacteria are likely the most simple organisms that are self sufficient and contain minimal code. They would just need nitrogen, phosphorus, water, carbon dioxide and sunlight.

TLDR: all organisms except primary producers are in some way parasitic when you consider that they rely upon the outputs of other organisms within their ecosystem

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Yes, even bacteria from u/FrostReaver 's answer is a parasite. Most organisms need something that was made by some other organisms. We divide life into things but because it's easier to analyze it that way, but they both depend on each other and influence each other (the same relationship as within parts of an organism).

So I wonder, is there any organism that if we put on say mars, it could function without any ecosystem? By function I mean not only survive but exponentially reproduce given available resources there. A follow up question would be if it would just deplete the resource it was feeding o and die after that, or could it bootstrap a whole ecosystem (theoretically, after many many millions of years).

How does this selection pressure tie in with the large amount of non-coding DNA in complex organisms?

Reading Wikipedia on this didn't leave me with the impression that there is consensus on the why of DNA that doesn't code for proteins or change transcription sites.

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Depends on your definition of an organism/virus, and what your function of interest is.

For example, if you're simply interested in things that can make more of themselves like viruses do: prions contain no genetic code at all and are simply misfolded proteins that cause other proteins of the same type to misfold into the same conformation.

Yeah the base pairs of RNA can spontaneously form in nature and RNA can act like an enzyme or protein itself. Last I heard, evidence strongly hints that the world was an RNA (single strand) world before double stranding and then the more stable DNA double helix developed. But it's not conclusive.

Plasma and RBCs both can cause issues as while RBCs have the antigens that the donee can target and destroy, plasma has the antibodies ro do that. That's why someone with 0 can't be given AB RCSs - they will have the antibodies against these cells and the cells will get shredded.

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