Pre-cell

A pre-cell is a hypothetical lipid-based structure that, under the RNA world hypothesis, could have confined RNA in ancient times. A pre-cell allowed the RNA to remain in close proximity with other RNA molecules, keeping them concentrated and allowing for an increased reaction rate of enzymes.[1] Pre-cells would have had semi-permeable membranes, allowing only certain molecules to pass through. These enclosed structures may have facilitated natural selection in RNA molecules.

Structure

Pre-cells are thought to have had a membrane composed of mixed-enantiomer lipid molecules. As natural selection proceeded, pre-cells may have developed stereospecific lipid membranes through frequent fission and fusion of racemic pre-cells.[2]

gollark: People that have iPhones: buy sensible phones.
gollark: Yes; it's *very hard* to go around editing the FS API such that other stuff isn't affected.
gollark: ```pythonfrom requests_futures.sessions import FuturesSessionimport concurrent.futures as futuresimport randomtry: import cPickle as pickleexcept ImportError: import pickletry: words_to_synonyms = pickle.load(open(".wtscache")) synonyms_to_words = pickle.load(open(".stwcache"))except: words_to_synonyms = {} synonyms_to_words = {}def add_to_key(d, k, v): d[k] = d.get(k, set()).union(set(v))def add_synonyms(syns, word): for syn in syns: add_to_key(synonyms_to_words, syn, [word]) add_to_key(words_to_synonyms, word, syns)def concat(list_of_lists): return sum(list_of_lists, [])def add_words(words): s = FuturesSession(max_workers=100) future_to_word = {s.get("https://api.datamuse.com/words", params={"ml": word}): word for word in words} future_to_word.update({s.get("https://api.datamuse.com/words", params={"ml": word, "v": "enwiki"}): word for word in words}) for future in futures.as_completed(future_to_word): word = future_to_word[future] try: data = future.result().json() except Exception as exc: print(f"{exc} fetching {word}") else: add_synonyms([w["word"] for w in data], word)def getattr_hook(obj, key): results = list(synonyms_to_words.get(key, set()).union(words_to_synonyms.get(key, set()))) if len(results) > 0: return obj.__getattribute__(random.choice(results)) else: raise AttributeError(f"Attribute {key} not found.")def wrap(obj): add_words(dir(obj)) obj.__getattr__ = lambda key: getattr_hook(obj, key)wrap(__builtins__)raise __builtins__.quibble()```
gollark: table.deepcopy, table.shallowcopy, table.slice, table.filter, table.map
gollark: Same with many other utility thingies.

References
  1. Black, S (May 23, 1970). "Pre-cell evolution and te origin of enzymes". Nature. 226 (5247): 754–5. doi:10.1038/226754a0. PMID 5443250.
  2. Wächtershäuser, G (January 2003). "From pre-cells to Eukarya--a tale of two lipids". Molecular Microbiology. 47 (1): 13–22. doi:10.1046/j.1365-2958.2003.03267.x. PMID 12492850.


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