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Digestion: Is there a chemist in the house?



I am contemplating preparing a classroom activity that would demonstrate how a
handful of dinosaurs may have collected and digested their food.  I would of
course start with skeletal reconstructions, tooth casts, gut contents,
_Scipionyx samniticus_, gastrolith and coprolite photographs and go from
there, using analogies such as rakes for sauropod teeth and shears for
_Triceratops_ chompers (pardon the vernacular).

Unfortunately, I don't have a bear trap for the _T. rex_ analog (though I
would be interested in a source for railroad spikes as a reasonable
alternative) and I cannot think of any man-made tool which functions quite
like the head of _Suchomimus_ in catching fish!  People have been doing demos
like this for some time for bird beaks, but some of these non-avian dinosaurs
are a bit more demanding!  Any ideas?

Ultimately, I'd like to take the food all the way through the digestive tract,
so this would require demonstrating the process of enzymes breaking down
starch, sugar, or protein, acids breaking down meat and bone, and yeast (as a
classroom friendly substitute for bacteria) fermenting food and producing
carbon dioxide gas.  (I have already obtained a collection of river rocks for
the gizzard).

Having seen an old episode of the PBS program "3-2-1 Classroom Contact"
entitled "Digestion: the Inside Story," I know that it is possible to show an
enzyme solution rapidly dissolving a french fry, and an acid and enzyme
solution rapidly dissolving a piece of meat (possibly liver), but I can find
no source for information on precisely how I can achieve these feats myself.
I also intend to avoid the use of slaughtered animal guts in the classroom,
informative though they may be.  (The program showed what the food looked like
inside the stomach and intestines of a pig, revealing the changes in
consistency as the food progressed through the digestive tract).

I have found a number of on-line directions for classroom experiments which
use enzymes, acids, and yeast, but these only provide indirect information
such as "Try different cleaning products which contain enzymes," "Try
different temperatures," "Try lemon juice and vinegar," and then "Wait for a
couple of days" and "See what happens."  I would need to see more immediate
results than that, as I would like to get through the activity in a single
session.  No doubt, the lesson plans I have found to date are written in an
open ended fashion to encourage the students to work things out for
themselves, and the agents involved are not highly reactive, thus avoiding the
issue of providing children with hazardous materials (such as sulfuric acid).
As I am planning on a classroom activity rather than an experiment, my issues
and modus operandi would differ.  For example, I would handle the acid portion
of the activity myself.  (And, no, I will not bring any full grown gharials /
gavials into classrooms, even though it would be fun).  :^)

I can, of course, prepare some things ahead of time: a floppy bone which has
soaked in vinegar for a week, for instance.  Still, I would like to hear from
anyone who can tell me how to demonstrate _spontaneous digestive activity_
with acids, enzymes, and yeast.  If you feel that this information would be
too dangerous for general list "consumption," please contact me off-list.

I did mention dinosaurs, didn't I?

-- Ralph W. Miller III       gbabcock@best.com

If you are what you eat, then you must be an Anthropophagus.