X-Message-Number: 21123
Date: Tue, 11 Feb 2003 05:40:48 -0800
From: James Swayze <>
Subject: Red blood cells vs Respirocytes
References: <>

> Message #21107
> Date: Mon, 10 Feb 2003 21:15:02 +1100
> From: Philip Rhoades <>
> Subject: Re: biological organisms eating diamond
> References: <>
>
> Henri,
>
>

<snip>

>
> In terms of a total system, this is not likely to be true - I have had
> some experience with virtual organisms and ones that have "evolved"
> through "natural selection" routinely outclass human "designed" ones
> for particular features.  But even with "evolved" artifical designs you
> are still probably being a bit optimistic about humans understanding
> _everything_ about the most complex system in the universe (that we
> know of) and designing artifical replacements for _all_ of the
> different bits.  eg you mentioned red blood cells and gas carrying
> capacity but red blood cells do other things besides carry gas (eg they
> act as "bricks" in clotting blood).  To simply replace red blood cells
> with a (much smaller?) artificial respirocyte might keep the gases
> moving but you might bleed to death from millions of micro haemorrhages
> that are occurring constantly.
>

> Message #21110
> Date: Mon, 10 Feb 2003 07:33:50 -0500
> From: Thomas Donaldson <>
> Subject: CryoNet #21092 - #21100
>
> For Mr. Kluytmans:
>
>

<snip>

>
> As for red blood cells, they are more than bags of hemoglobin. They
> also act to control blood viscosity, convert CO2 to bicarbonate,
> and have their own metabolic system to do these functions. Their
> flat shape gives a much larger surface for gas to diffuse in and
> out of them. They also cause turbulence in the blood stream, which
> helps them diffuse out oxygen and intake CO2. No, they have no
> nucleus and are created in our marrow from other cells (do Freitas's
> versions self-reproduce? How are they made?).
>
> If your nanomachines perform only one function, then you will have
> to have many more to do the tasks of an enzyme. I would say the
> same for devices which transport oxygen and remove CO2. And don't
> come back at me saying that the other functions of red blood cells
> would no longer be needed: unless you give me the complete
> metabolism of the entire system you want to build with your
> diamandoid nanosystems then you haven't established that even
> Freitas's "blood cells" would really work when tried as a
> substitute... or in a complete system.


To those arguing red blood cells vs Respirocytes I think perhaps somewhere, and 
I don't know where, a misunderstanding has crept in. It is not my understanding 
that Frietas intends to competely replace red blood cells or in fact even 
replace _any_ red blood cells at all but rather it was my understanding he means
to augment their oxygen/CO2 transfer capabilities only. This makes some 
arguments moot I do believe.

Just my two cents.

James
--
Cryonics Institute of Michigan Member!
The Immortalist Society Member!
The Society for Venturism Member!


MY WEBSITE: http://www.geocities.com/~davidpascal/swayze/ While there follow the
links to photos of me and some of my artwork and a radio interview on Dr.  J's 
ChangeSurfer Radio program with me and the father of cryonics Prof.  Robert 
Ettinger, author of "The Prospect of Immortality".
A RELIGION I actually recommend: http://www.venturist.org
A FAVORITE quote: Last lines of the first Star Trek the Next Generation movie.

Capt.  Picard: "What we leave behind is not as important as how we've lived, 
after all Number One, we're only mortal."
Will Ryker: "Speak for yourself captain, I intend to live forever!"

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