There is plenty of stuff on the web, but to get you started, here are some things to get you thinking about how abiogenesis may have occurred, or at least suggest the workings of some steps along the way.
1) In 1953, Stanley Miller, working under Harold Urey, showed that amino acids are able to form spontaneously in the conditions which may have existed in earth's primordial atmosphere. In three months, his experiment produced at least 7 amino acids, which included 3 of the 20 found in modern (and probably ancient) organisms. (Amino acids are the 'building blocks' of all proteins).
2) Certain lipid molecules, including phospholipids (the main type of molecule that makes up cell membranes), will spontaneously form a number of structures when placed in water, eg "micelles" and "bi-layers".
Micelles are tiny spherical structures made of relatively few molecules, and can 'carry' other molecules inside them, although I'm am not aware of the significance of this.
Bi-layers are often much larger structures capable of forming large sheets, or "membranes" which can be quite bendy and stretchy. They can even bend around on themselves to form massive. spherical "containers" which separate their contents from the outside world and thus allows the contents to become significantly chemically different. This is exactly the structure used by all living cells to contain the vast array of chemical reactions that need to be carried out under special chemical conditions.
The significance of spontaneous organisation of certain lipids is that it is thermodynamically favourable for these structures to occur and therefore plausible that they played an important part in containing the first biochemical interactions that occurred during abiogenesis.
3) It has also been suggested that certain clay substrates may have formed a biochemical "staging ground" for collecting and organising biologically significant molecules. I remember reading (possibly in a Richard Dawkins book) about one theory which suggested the idea that the clay substrates themselves could have been self-reproducing. The premise of this particular theory is that imperfections in some crystal structures are often repeated throughout the crystal as it grows. Therefore crystal structures with certain imperfections may have encouraged more of themselves to exist. Furthermore, the theory says, if particular "self-replicating" crystal structures gave rise to large scale properties that further encouraged the production of these crystals, then they would become even more prolific. For example, if a certain "self-replicating" crystal was usually generated in still water, but also had the property that, when washed into slow-moving water, sediments of the crystal caused that slow-moving water to "dam up", then the water would become still again, thus creating an environment suitable for creating more of the crystal.
Far-fetched? Perhaps, But I am always wary of criticising a theory simply because of my own incredulity.
Anyway. The upshot is that we are a number of theories of abiogenesis out there, none of them at all complete. I guess that any theories will remain speculative until we are able to satisfactorily string together a series of observeda and reproducible reactions and interactions that would be able to explain abiogenesis.
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There is plenty of stuff on the web, but to get you started, here are some things to get you thinking about how abiogenesis may have occurred, or at least suggest the workings of some steps along the way.
1) In 1953, Stanley Miller, working under Harold Urey, showed that amino acids are able to form spontaneously in the conditions which may have existed in earth's primordial atmosphere. In three months, his experiment produced at least 7 amino acids, which included 3 of the 20 found in modern (and probably ancient) organisms. (Amino acids are the 'building blocks' of all proteins).
2) Certain lipid molecules, including phospholipids (the main type of molecule that makes up cell membranes), will spontaneously form a number of structures when placed in water, eg "micelles" and "bi-layers".
Micelles are tiny spherical structures made of relatively few molecules, and can 'carry' other molecules inside them, although I'm am not aware of the significance of this.
Bi-layers are often much larger structures capable of forming large sheets, or "membranes" which can be quite bendy and stretchy. They can even bend around on themselves to form massive. spherical "containers" which separate their contents from the outside world and thus allows the contents to become significantly chemically different. This is exactly the structure used by all living cells to contain the vast array of chemical reactions that need to be carried out under special chemical conditions.
The significance of spontaneous organisation of certain lipids is that it is thermodynamically favourable for these structures to occur and therefore plausible that they played an important part in containing the first biochemical interactions that occurred during abiogenesis.
3) It has also been suggested that certain clay substrates may have formed a biochemical "staging ground" for collecting and organising biologically significant molecules. I remember reading (possibly in a Richard Dawkins book) about one theory which suggested the idea that the clay substrates themselves could have been self-reproducing. The premise of this particular theory is that imperfections in some crystal structures are often repeated throughout the crystal as it grows. Therefore crystal structures with certain imperfections may have encouraged more of themselves to exist. Furthermore, the theory says, if particular "self-replicating" crystal structures gave rise to large scale properties that further encouraged the production of these crystals, then they would become even more prolific. For example, if a certain "self-replicating" crystal was usually generated in still water, but also had the property that, when washed into slow-moving water, sediments of the crystal caused that slow-moving water to "dam up", then the water would become still again, thus creating an environment suitable for creating more of the crystal.
Far-fetched? Perhaps, But I am always wary of criticising a theory simply because of my own incredulity.
Anyway. The upshot is that we are a number of theories of abiogenesis out there, none of them at all complete. I guess that any theories will remain speculative until we are able to satisfactorily string together a series of observeda and reproducible reactions and interactions that would be able to explain abiogenesis.