🚀 go-pugleaf

TODD J PIERCE wrote:
> 
> I know I can see individual strands of bacteria at 100x with a microscope.
> 
> My question is this what magnification do I need to see both a cell and
> its nucleus--that is, for a fairly large cell--200x, 500x?  In our very
> basic lab, we have microscopes up to 100x.  Are microscopes with higher
> ranges of magnifacation common in working labs?
> 
> Could I see the nucleus with the standard microscope, or can one only see
> the dark outline of the nucleus with an electron microscope?
> 
> Thanks,
> Todd

If you want to locate the nucleus you want it to call out to you above
background.  Use a fluorescent stain for double strand nucleic acid. 
Will ethidium bromide (toxic!) do it (under near-UV illumination)?  Ask
the experts:  http://www.probes.com/ 

Visualizing cell nuclei and chromosomes arrested by Colcemide(tm) or
colchicine is standard operating procedure.  It doesn't require anything
beyond an optical microscope.  Observing onion root tip chromosomes this
way is a high school lab prep.

-- 
Uncle Al Schwartz
UncleAl0@ix.netcom.com ("zero" before @)
http://pw2.netcom.com/~uncleal0/uncleal.htm
http://www.ultra.net.au/~wisby/uncleal.htm
http://www.guyy.demon.co.uk/uncleal/uncleal.htm
 (Toxic URLs! Unsafe for children, Democrats, and most mammals)
"Quis custodiet ipsos custodes?"  The Net!

In sci.chem Uncle Al <UncleAl0@ix.netcom.com> wrote:
: TODD J PIERCE wrote:
Sorry Todd....You're OK

: If you want to locate the nucleus you want it to call out to you above
: background.  Use a fluorescent stain for double strand nucleic acid. 
: Will ethidium bromide (toxic!) do it (under near-UV illumination)?  Ask
: the experts:  http://www.probes.com/ 

: Visualizing cell nuclei and chromosomes arrested by Colcemide(tm) or
: colchicine is standard operating procedure.  It doesn't require anything
: beyond an optical microscope.  Observing onion root tip chromosomes this
: way is a high school lab prep.

Keep this shit out of sci.chem you addleplated dejanews junkie.  

Should you persist we will set eraserbots loose on the net to
wipe out any trace of your ill-begotten self...We will track
you down and inject you with brain clumping prions.  
Hospitals will be instructed to provide you with only
blood transfusions from tubercular seriopositive chemists,
whose mothers will gather daily to spit on you. So,....

Keep this biology shit out of sci.chem, which is only for
the pure......

josh halpern

TODD J PIERCE wrote:
> 
> I know I can see individual strands of bacteria at 100x with a microscope.
> 
> My question is this what magnification do I need to see both a cell and
> its nucleus--that is, for a fairly large cell--200x, 500x?  In our very
> basic lab, we have microscopes up to 100x.  Are microscopes with higher
> ranges of magnifacation common in working labs?
> 
> Could I see the nucleus with the standard microscope, or can one only see
> the dark outline of the nucleus with an electron microscope?
> 
> Thanks,
> Todd


Ok, I'll ask the obvious question: are you talking about eukariotic cells,
which have "true" nucleii or are you still talking about bacteria, which lack
true nucleii? (many bacteriologists will still refer to the "nucleoid body" or
whatever as the "nucleus;" the semantics of this are not really important.  I
just want to make sure I answer the right question).

If eukariotic cells are the subject and you want to see the outline of the
nucleus during metaphase, a decent phase-contrast scope will suit fine. 
Magnification of 100X will also be fine for this.

Now, if you want to see the nucleoid body (that is, the chromosome) of a
bacterial cell, you will more magnification (say, 300x or so) would be helpful
and you will need to do something to make the DNA stand out.  Another poster
suggested a fluorescent dye, which is the best approach, although I wouldn't
use ethidium bromide (DAPI or one of the Hoescht dyes are better for
epifluorescence).  This will require a much more elaborate scope, since you
need to have the ability to hit the cells through the objective itself with
the excititory wavelength to see them (that is what's called "epifluorescence").

Finally, as for what a "working lab" might have, it really depends on the
style of research.  I would say that a phase scope with magnification around
200-300x is commone to any lab doing mammalian cell culture.  More elaborate
optical systems also are common depending on the focus of the lab.  eg, any
nematode lab (the nematode C. elegans is a really popular developmental
genetics model) will have one or more scope equiped with differential
interference contrast (or "Nomarski") optics and magnifications out to 300X or
more.  These same scopes often are equiped for epifluorescence.  Even more
elaborate setups like confocal microscopes are getting more common. 

-- 
-tony


*********************************************************

Anthony J. Pelletier, Ph.D.
Assistant Professor, Department of Cell Biology
The Scripps Research Institute
Mail stop SBR12
10550 North Torrey Pines Rd.
La Jolla, CA 92037
(619) 784-9760

anthonyp@scripps.edu

In article <6c89tf$9u0@nnrp4.farm.idt.net>, Joshua Halpern <jbh@IDT.NET>
writes
>In sci.chem Uncle Al <UncleAl0@ix.netcom.com> wrote:
>: TODD J PIERCE wrote:
>Sorry Todd....You're OK
>
>: If you want to locate the nucleus you want it to call out to you above
>: background.  Use a fluorescent stain for double strand nucleic acid. 
>: Will ethidium bromide (toxic!) do it (under near-UV illumination)?  Ask
>: the experts:  http://www.probes.com/ 
>
>: Visualizing cell nuclei and chromosomes arrested by Colcemide(tm) or
>: colchicine is standard operating procedure.  It doesn't require anything
>: beyond an optical microscope.  Observing onion root tip chromosomes this
>: way is a high school lab prep.
>
>Keep this shit out of sci.chem you addleplated dejanews junkie.  
>
>Should you persist we will set eraserbots loose on the net to
>wipe out any trace of your ill-begotten self...We will track
>you down and inject you with brain clumping prions.  
>Hospitals will be instructed to provide you with only
>blood transfusions from tubercular seriopositive chemists,
>whose mothers will gather daily to spit on you. So,....
>
>Keep this biology shit out of sci.chem, which is only for
>the pure......
>
>josh halpern
>

Where do the biochemists go then ?

-- 
Mike H
        
        "If truth equals concensus and the populace is wrong....
                - I am still condemned"

N.B. Remove ".spamless" from address to reply.

Mike H wrote:
> 
> In article <6c89tf$9u0@nnrp4.farm.idt.net>, Joshua Halpern <jbh@IDT.NET>
> writes
> >In sci.chem Uncle Al <UncleAl0@ix.netcom.com> wrote:
> >: TODD J PIERCE wrote:
> >Sorry Todd....You're OK
> >
> >: If you want to locate the nucleus you want it to call out to you above
> >: background.  Use a fluorescent stain for double strand nucleic acid.
> >: Will ethidium bromide (toxic!) do it (under near-UV illumination)?  Ask
> >: the experts:  http://www.probes.com/
> >
> >: Visualizing cell nuclei and chromosomes arrested by Colcemide(tm) or
> >: colchicine is standard operating procedure.  It doesn't require anything
> >: beyond an optical microscope.  Observing onion root tip chromosomes this
> >: way is a high school lab prep.
> >
> >Keep this shit out of sci.chem you addleplated dejanews junkie.
> >
> >Should you persist we will set eraserbots loose on the net to
> >wipe out any trace of your ill-begotten self...We will track
> >you down and inject you with brain clumping prions.
> >Hospitals will be instructed to provide you with only
> >blood transfusions from tubercular seriopositive chemists,
> >whose mothers will gather daily to spit on you. So,....
> >
> >Keep this biology shit out of sci.chem, which is only for
> >the pure......
> >
> >josh halpern
> >
> 
> Where do the biochemists go then ?

sci.chem

If you want to discuss extracting the essence of immortality from
stained skivvies, sci.envrionment

-- 
Uncle Al Schwartz
UncleAl0@ix.netcom.com ("zero" before @)
http://pw2.netcom.com/~uncleal0/uncleal.htm
http://www.ultra.net.au/~wisby/uncleal.htm
http://www.guyy.demon.co.uk/uncleal/uncleal.htm
 (Toxic URLs! Unsafe for children, Democrats, and most mammals)
"Quis custodiet ipsos custodes?"  The Net!