Mitotic spindle and magnetic poles.

Obwon ob110ob at att.net
Wed Jan 21 14:37:54 EST 2004


Upon examination of the page

http://science.kennesaw.edu/~mhermes/cisplat/cisplat01.htm

 I noted that the items in image "c" bend in
counterintuitive ways.  I would add that fact, to the
magnitude of magnitism needed to induce any change, and am
forced to summarily conclude that the effects being
discussed, are most likely controled by internal, rather
than external, events.  It would seem that the events are
produced by prehensile spindles, attempting to complete a
predetermined tasks of aligning with another body of like
design. 

  That suggests that a "natural" path is configured as the
simplest path, and that; that just happens to coincide with
something else found in nature that also performs the same
task, at least superficially.  

  I can easily imagine that were it not so, with all the lab
work that has been performed over the last half century,
while electricity and magnetism has been notoriously
present in the lab, something along your line of reasoning,
would not yet have been noticed.

  Obwon

  

  


On 25 Nov 2003 15:22:44 -0800, rgregoryclark at yahoo.com
(Robert Clark) wrote:

>On the Yahoo discussion group on Cellbiology, 
>http://groups.yahoo.com/group/cellbiology/ , someone posted a link to
>research establishing an effect of strong magnetic fields on the
>division process:
>
>Powerful magnetic field forces living cells to change.
>"Writing in the Proceedings of the National Academy of Sciences, the
>researchers suggest that the magnetic field forced cellular protein
>ropes, called microtubules, to orient parallel to it, re-orienting the
>cleavages. A microtubule is a cellular structure, part of what is
>called the mitotic spindle apparatus, which normally determines
>cleavage direction.
>"The microtubules re-orient in a similar way as a compass needle turns
>along magnetic north. Unlike the iron in a compass needle, the Earth's
>weak magnetic field is insufficient to cause the microtubules to
>realign. The materials composing the microtubules and the rest of the
>frog eggs respond very weakly to magnetic fields. This weak response
>is probably at the root of disagreements among scientists about
>whether steady magnetic fields affect living things, the researchers
>said. Their study shows that a huge magnetic field, more than 100,000
>times as strong as Earth's, will affect the eggs."
>http://www.brown.edu/Administration/News_Bureau/1998-99/98-098.html
>
> The full text of the PNAS article is available here:
>
>Cleavage planes in frog eggs are altered by strong magnetic fields 
>(cell division/mitotic apparatus/microtubules/Xenopus) 
>James M. Denegre*, James M. Valles Jr., Kevin Lin, W. B. Jordan, and
>Kimberly L. Mowry
>PNAS, Vol. 95, Issue 25, 14729-14732, December 8, 1998
>http://www.pnas.org/cgi/content/full/95/25/14729
>
> There are links to similar research on this page.
>
> After a web search I also found this:
>
>Cisplatin
>1. Study of the Effect of Electric Fields on E. coli
>http://science.kennesaw.edu/~mhermes/cisplat/cisplat01.htm
>
> 
>   Bob Clark
>
>
>-------------------------------------------------------------
>For email response, send to same userid as above, but append
>Hotmail.com instead of Yahoo.com.
>-------------------------------------------------------------
>
>
>r norman <rsn_ at _comcast.net> wrote in message news:<cfn6sv4nnfcku5egat51kuvm8t4btcq370 at 4ax.com>...
>> On 24 Nov 2003 22:06:58 -0800, rgregoryclark at yahoo.com (Robert Clark)
>> wrote:
>> 
>> >Has there been any investigation of the possibility that the origin of
>> >the mitotic spindle really is due to electromagnetism?
>> > Compare the image on this page:
>> >
>> >Media: Mitotic Spindle.
>> >http://www.meta-library.net/media/mitspin-body.html
>> >
>> > To the first image on this page:
>> >
>> >Magnetism.
>> >http://www.warren-wilson.edu/~physics/physics2/Formal_2001/BenWarren/formallab%25202.htm
>> >
>> 
>> There is no reason to believe magnetism is a mechanism just because
>> the pictures look similar.  Look at the electric field of a dipole
>>   http://hyperphysics.phy-astr.gsu.edu/hbase/electric/dipole.html
>> to see the same thing.
>> 
>> The similarty in shape is caused by processes which share some
>> superficial similarities but major differences  For the similarities,
>> first, there are two separate "organizing centers": the spindle poles
>> for mitosis, and the two poles of a magnetic or electric dipole.  At
>> each organizing center there is a tendency for lines to radiate from
>> the center in all directions.  In both the magnetic and the electric
>> dipoles, the tendency is to radiate outward from one of the poles but
>> to radiate inward into the other pole.  The result is the
>> spinde-shaped pattern of field lines.  There really are strong
>> parallels between the magnetic and the electric dipoles -- one pole
>> radiates out, the other radiates in.  Add the two together and you get
>> the result.
>> 
>> In the spindle, the process is very different.  The spindle fibers
>> radiate outward from both poles.  Some of these, the astral fibers,
>> always remain that way.  These do not look at all like the magnetic or
>> electric dipole lines but look more like a magnetic or electric
>> monopole.  Others meet (either by direct contact as in the polar
>> fibers or by connecting to the same chromosome in the kinetochore
>> fibers).  These fibers tend to spread out from one pole and then
>> rejoin at the other, and so sort of look like the field lines of the
>> magnetic or electric dipole.  Since the fibers that attach to the
>> chromosomes are the "important" ones, they are the ones shown in all
>> the diagrams. 
>> 
>> So in this case, the similarity is really superficial.  However, the
>> cause of science is always furthered by trying to find relationships
>> between seemingly very different things -- so keep looking and keep
>> asking!



O[]ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ[]O
"Those who can make you believe absurdities can 
make you commit atrocities."
                              - Voltaire
O[]ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ[]O



More information about the Bioforum mailing list