BFett wrote:Have scientists been able to construct a living cell through the use of chemicals?
You make it sound very easy to create a cell. If that were the case, scientists should have the ability to create living cells that are extremely simple.
By living I mean capable of reproduction, has gas exchange, and grows.
If scientists haven't been able to create these bacteria out of chemicals then the rest of your argument Outlander, doesn't hold water
I'm a bit late to the party, but well. I believe that Dino addressed most of your questions in a more than satisfactory fashion ( great job Dino!
), so I'll only add a little bit of information to the biology part.
As others already mentioned, research on origin of the cell is an on-going process. We haven't quite figured it out. However, we managed to achieve:
-
a self-replicating ribozyme - basically, a piece of RNA that copies itself given that it has basic materials such as nucleotides (which were present in the primordial soup) - I think that it's not in the free access, though;
- research on self-organisation of lipids is quite extensive, so here's a
video of a simulation of the lipid bi-layer self-assembly. It's a course-grain, slowed down simulation; the actual process happens in
nanoseconds (although those are lipids optimised for self-assembly; naturally occurring ones take much longer - that is, milliseconds to seconds range;
-
this article (earlier cited by Cornflakes) is opened for access; it's a nice review of what has been done by one of the best teams in the field. It's a bit out-dated, but is nonetheless very good;
- there has been an experiment about making a fully synthetic DNA and inserting it into a cell deprived of DNA, creating an
'artificial' organism; however, it's only partially synthetic, and the genes are mostly the same as in the naturally occurring bacteria it was built upon, so I'd say it's an exercise in futility. Cool methods of working with a cell, though - it'll surely come handy in the future, and that's the true worth of that work.
Now, scientists are generally quite reluctant to start unethical experiments such as creating new life or making an AI - the whole 'playing God' thing is uncomfortable, and bioethics department would eat us alive for even thinking about most of this stuff.
Another problem with creating bacterial life from the scratch is about times involved. Now, there are some really long experiments such as in the field of botany where it can take decades, or the
Soviet project to domesticate foxes, but leaving some primordial soup to self-assemble into primitive RNA replicators inside lipid micelles and leave it to evolve for a while is on the timescale of many millions of years. Instead, it's better to replicate each step of the proto-cell evolution, and find concrete evidence of the processes that allowed it to change.
So, we aren't magicians, we are only trying our best.
I see this thread grew into
an orgy a party again...I'll go read those new pages, maybe there are more things I can address
Edit: the main point of my big post on the origins of the cell was to show that life is allowed to appear because of the basic chemical and physical properties of the matter. Whether or not it will appear on a given planet is a question of chance and luck.
People also mentioned alternative biochemistries (silicon-based; there's also ammonia-based) - well, those are closer to the improbable scale, because chemistry limits them much more than us carbon-based folks. They might exist, but are likely to be very, very rare, as they need a very special set of circumstance to arise.
Survivor of the Josh Parnell Blackout of 2015.