On 1/13/2011 2:49 AM, Invisible wrote:
>>> The distinction you're looking for is between eukaryotes and
>>> non-eukaryotes.
>>>
>> Uh, yeah. Couldn't think of the proper term though. But, the rest is
>> correct. If you don't have excess resources to waste on messing with
>> extra baggage, you don't live long if you have it. If you do have the
>> "power plants", you can afford to waste more space in the genome on
>> things that don't work, duplicate results, etc.
>
>>> I'm not sure I actually agree with this assessment.
>>>
>> http://scienceblogs.com/pharyngula/2010/12/how_to_afford_a_big_sloppy_gen.php
>>
>>
>> As to the cite for prokaryotes not having as many copy errors, I think
>> it would be more accurate to say, "They don't *preserve* as many." If
>> they did, they would have way more junk DNA, which is precisely what
>> they can't afford to have laying around in the first place. The actual
>> number of such errors that happen is likely the same, but, when it comes
>> to costs, if you can't afford them, you don't see those copied chunks
>> sticking around long.
>
> I think we need to distinguish between DNA that isn't used for anything,
> and DNA which actually produces proteins, but they don't do anything
> really useful.
>
> Just having a sequence in your genome doesn't really cost that much.
> Synthesizing it into a protein is much more expensive.
>
> It wouldn't surprise me if non-eukaryotes have fewer genes turned on,
> and possibly smaller genomes, but I doubt that they have radically
> "cleaner" genomes.
You are forgetting that you *still* have to copy all that extra stuff, 
when ever you divide the cell, so there is still a cost to synthesize 
all the copies, before the cell splits to form new cells. Also, its not 
a simple case of, "just ignore the stuff I don't use", something has to 
run through the pattern, decide what needs to be unfolded, or folded, 
jump past any stuff that is folded into an unusable state, etc.

And, most of the code, unlike in multi-celled organisms, is going to be 
"on". There is no reason to turn parts off, except for mitosis, and the 
like, if you are not differentiating the cells, which requires shutting 
off the parts you don't need running at all. Something that has a mess 
of extra code is going to have a lot of stuff the maneuver around to get 
anything done, and those that don't, are not likely to have a lot of 
inactive code, which isn't doing synthesis, more or less massively 
parallel, constantly.

-- 
void main () {

     if version = "Vista" {
       call slow_by_half();
       call DRM_everything();
     }
     call functional_code();
   }
   else
     call crash_windows();
}

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