Need an answer for my son

[Dawn, Douglas]

Paul, I'll give it a shot:

You got me curious to the differnces on the digestive systems of
Lepidoptera.  While most ingest simple sugars, some "sip" mud and other
even more interesting more complex nutritional sources (Pollen,
Ejaculate, Sweat, etc.) to live longer.  Can someone recommend a
complete, in print source with a good scientific review on Leps
regarding this?

Regarding your original question:  If you stop to think about it,
digestion must be a complex process, and not similar to the burning of
gas to its ultimate components in what is basically a one step and final
process for the purposes of gas and the motor.

With all the specialized proteins, cofactors, etc. floating around in
the digestive medium, (after cooking and marinating, which also digest
by some terminology), it is not hard to imagine proteins or lipid
structures binding certain protein fragments and being picked up by the
blood and transported to other locations in the body for use or
modification.

Unfortunately I do not have a Biochemistry Book handy to give a more
authoritative answer (Biochemistry by Stryer would be excellent), the
trusty Webster's New World Dictionary mentions the etymology for
"vitamin" as amines necessary for life, coming from the mistaken
original concept that all vitamins contain amino acids, the building
blocks of proteins.

While vitamins may generally have some or a lot of protein structure, I
think that it is more important to focus on the metals, inorganic
complexes, fatty components that are also present, when one thinks of a
generic vitamin.  Other components such as metals in certain inorganic
complexes and oxidation state which the body needs could easily be bound
and transported to places of need.

Of course, digestion doesn't pull apart some tissues (at least, probably
lipid based) since our stomachs and other areas involved in digestion
are able to contain the processes without digesting neighboring tissues.

Finally, the body does produce some vitamins from scratch.  Eating a
well balanced diet would insure that you have all the parts to build the
vitamins you need, whether or not they were broken down first totally,
partially, linked or otherwise modified, or used exactly as ingested.

Hope this helps.  It is not really in black and white, but I can't think
of one instance where body chemistry is.  That's why I prefer Leps.
While their biochemistry debateably may not be less complex, at least
the small size gives the appearance that their is less to worry about
toward the goal of have an understanding.

Saludos
Doug Dawn
stelenes at pobox.com
Monterrey, Mexico
 ----------
>>>From: Paul M. Sammut
>>>To: leps-l at lists.yale.edu
>>>Subject: Need an answer for my son
>>>Date: Miercoles 10 de Diciembre de 1997 9:44AM
>>>
>>>Hi Friend of the Net,
>>>
>>>	Excuse my posting this query to this newsgroup, to which I also belong.
>>>However I am sure out there somebody will help me out with this problem.
>>>
>>>Question which my son put to me:
>>>
>>>Are vitamins, which are proteins, digested in the alimentary with the
>>>rest of the food? If yes, then all the vitamins we take in are destroyed
>>>before they can be utilised by the body. What actually happens to the
>>>vitamins in food during digestion?
>>>
>>>Beleive me I could not come up with a convincing answer. Please be kind
>>>and helpful. Regards to all, Paul.
>>>
>>>Paul Sammut
>>>MALTA
>>>
>>>