Sujet : Re: Irony
De : {$to$} (at) *nospam* meden.demon.co.uk (Ernest Major)
Groupes : talk.originsDate : 16. Dec 2024, 19:50:00
Autres entêtes
Organisation : A noiseless patient Spider
Message-ID : <vjpson$1899g$1@dont-email.me>
References : 1
User-Agent : Mozilla Thunderbird
On 16/12/2024 06:10, MarkE wrote:
I've raised Steven Benner's "tar paradox" in a recent post; it subsequently occurred to me that the Miller-Urey experiment is, ironically, a demonstration of this (I've mentioned this in a another thread, but thought it deserved a separate post). Miller-Urey produced only unusable small/trace amounts of amino acids in a "tar" mixture:
Breakdown of products:
* Carboxylic Acids (e.g., formic acid, acetic acid, and succinic acid): These dominated the product mix, typically making up 80-90% of the total organic compounds.
Not tar. I found a Miller & Urey paper.
* Hydroxy Acids (e.g., lactic acid and glycolic acid): Accounted for 5-10% of the total.
Not tar.
* Amino Acids: Typically contributed about 1-2% of the total organic product yield.
Not tar. Also the numbers you give below add up to ~4.5%. The number from a Miller and Urey paper I found give an every larger proportion (by mole) of amino acids, and carboxylic acids in the 50-60% range.
* Other Organic Molecules: Small amounts of urea, nitriles, aldehydes, and hydrocarbons were also formed, constituting the remainder of the products.
Not tar.
Relative concentrations of amino acids produced:
- Glycine: Approximately 2.1% of the total yield
- Alanine: Around 1.7%
- β-Alanine: About 0.76%
- Aspartic Acid: Approximately 0.024%
- Glutamic Acid: Around 0.051%
I had thought that the Miller-Urey experiment did produce appreciable quantities of tar. Was I mistaken?
-- alias Ernest Major